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entitled 'Preliminary Report on the Effects of COPS Funds on the 
Decline in Crime during the 1990s' which was released on July 7, 2005.

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United States Government Accountability Office: 

Washington, DC 20548: 

May XX, 2005: 

The Honorable F. James Sensenbrenner: 
Chairman: 
Committee on the Judiciary: 
House of Representatives: 

Subject: Preliminary Report on the Effects of COPS Funds on the Decline 
in Crime during the 1990s: 

Dear Mr. Chairman: 

Established under the Violent Crime Control and Law Enforcement Act of 
1994 (Pub. L. 103-322), which authorized appropriations of $8.8 billion 
for it, the Community Oriented Policing Services (COPS) program mission 
was to advance the practice of community policing as an effective 
strategy in communities' efforts to improve public safety and had as a 
goal providing for 100,000 new police officers. VCCLEA--the largest 
federal crime bill in the history of the country--was enacted during a 
period of increasing crime, particularly serious violent crimes, such 
as murder, rape, aggravated assault, and robbery.[Footnote 1] For 
example, between 1983 and 1992--the year before the national decline in 
crime began--the number of serious violent crimes known to the police 
increased from about 1.3 million to over 1.9 million (or about 50 
percent), and the serious violent crime rate per 100,000 population 
increased from 538 to 758 (or by 39 percent).

In 1994, the COPS Office began making grants to local law enforcement 
agencies, and by 2001, it had made about 23,000 grants totaling $7.3 
billion. Of these obligated amounts, by the end of 2001, local law 
enforcement agencies had expended (or drawn down) about $5 billion. The 
COPS grant expenditures amounted to about 1 percent of total local law 
enforcement expenditures between 1994 and 2001. At the same time that 
local agencies were drawing down COPS funds, serious crimes declined. 
For example, between 1994 and 2001, the number of violent crimes 
declined from about 1.9 million to about 1.4 million (or by 23 
percent), and the violent crime rate per 100,000 population declined 
from 714 to 504 (or by 29 percent). Given the comparatively large 
expenditure of COPS funds for local law enforcement and the correlation 
between these expenditures and the decline in crime, the questions of 
whether, and if any, how much, the COPS grants contributed to the 
decline in crime merits attention.

Yet, this issue has received only modest attention. One recent study 
concluded that the COPS grants contributed to reductions in crime in 
the 1990s. However, we previously reviewed the study and reported that 
its methodological limitations were such that the study's results 
should be viewed as inconclusive.[Footnote 2] Moreover, neither the 
study we reviewed nor another study of effects of COPS grant funds on 
crime attempted to isolate the ways in which COPS funds could affect 
crime.[Footnote 3] For example, the studies did not examine if COPS- 
funded police officers were associated with reductions in crime.

In response to our review of the prior study, you asked us to undertake 
our own independent evaluation of the impact of COPS grants on the 
decline in crime that occurred during the 1990s. This correspondence 
reports partial findings regarding three inter-related questions about 
the extent to which, if any, that COPS grants affected the decline in 
crime in the 1990s: (1) How were the COPS grant funds distributed among 
local law enforcement agencies, and to what extent did the distribution 
of funds correspond to the distribution of violent crime? (2) Did COPS 
grant funds lead to changes in the types of policing tactics that are 
associated with crime prevention? (3) Did COPS grant funds lead to 
increases in the number of sworn police officers, and if so, what was 
the impact of these COPS-funded officers on the decline in crime during 
the1990s? Our full report--due for release in the fall 2005--will 
address our research objectives in greater.

To address our reporting objectives, we created and analyzed a unique 
database consisting of observations on over 13,000 local law 
enforcement agencies covering the years from 1990 to 2001. For each 
agency, we compiled data on COPS and other federal law enforcement 
grant obligations and expenditures, crime rates, and sworn officers. We 
also compiled data on factors that the literature suggests are related 
to changes in crime, including local economic conditions--such as 
employment rates and per capita income--and demographic variables--such 
as the percent of the population aged 15 to 24, and the racial and 
gender composition of the population. We also added to the database 
information from two surveys of nationally representative samples of 
police departments that reported on the types of policing tactics that 
they implemented. Prior to developing our database, we assessed the 
reliability of each data source and in preparing this report, we used 
only the data that we found to be sufficiently reliable for the 
purposes of our report.

We analyzed the data on COPS and other federal grant obligation and 
expenditure amounts to describe how many agencies received COPS grants 
and the types and amounts of grants and expenditures. We compared the 
amounts of COPS grants with characteristics of each agency's community, 
such as their population size and crime rates. To address the extent to 
which COPS grants led to changes in policing tactics, we analyzed data 
from the two surveys to assess changes in policing tactics between 
agencies that received COPS grants and those that did not receive 
them.[Footnote 4] To assess the effects of COPS funds on officers and 
crime, we developed and estimated so-called fixed-effects regression 
models of these relationships. Our regressions estimated the effects of 
COPS and other federal law enforcement grants on officers and crime, 
respectively, while controlling for differences among agencies in their 
pre-COPS program trends in crime rates and sworn officers, differences 
over time in socio-economic factors that could affect both the number 
of police officers and crime rates, such as unemployment and per-capita 
income, and changes in population composition. To help to isolate the 
direction of causality between officers and crime, we used a 
statistical instrument, and to control for unmeasured sources of 
variation, we used agency, state, and year fixed effects. Because of 
the complexity of the statistical models that we used to estimate the 
effects of COPS grants on crime, we reviewed our approach and methods 
with a panel of expert researchers. The panel consisted of 
criminologists, economists, statisticians, and practitioners, and it 
was convened for us by the National Research Council. See enclosure I 
for additional details on our data and methods.

We conducted our work between November 2003 and May 2005 in accordance 
with generally accepted government auditing standards.

Background: 

The COPS Office distributed grants in some 36 different program 
categories. The largest grant program category was the COPS hiring 
grants, which required agencies to hire new officers and at the same 
time to indicate the types of community policing strategies that they 
intended to implement with the officers that they were to hire with 
these grants. The hiring grants paid a maximum of $25,000 per officer 
per year (or at most 75 percent of an officer's salary) and generally 
required that local agencies provide a match to cover the remaining 
salary and benefits. Agencies were also required to retain COPS-funded 
officers for at least one year after the end of the grant. COPS grants 
were also intended to encourage changes in policing practices. Agencies 
were asked to report the types of tactics that they planned to 
implement with their COPS hiring grants. Problem-solving that pertained 
to increased enforcement activities, place-oriented tactics that 
focused on addressing crime problems in specific buildings, 
neighborhoods or other places, and collaborating with community 
residents by increasing officer contact with citizens and improving 
citizen feedback were among types of tactics adopted.

In addition to COPS hiring grants, there were several other major 
categories of COPS grants programs. Making Officer Redeployment 
Effective (or MORE) grants were used to purchase equipment and hire 
civilians, with the goal of expanding the amount of time current law 
enforcement officers can spend on community policing.[Footnote 5] Some 
COPS grant programs provided funds for innovations in policing. For 
example, the Distressed Neighborhoods Pilot Project grants provided 
funds to communities with high levels of crime and/or economic distress 
to hire officers and implement a variety of strategies to improve 
public safety, and the Methamphetamine Initiative provided funds to 
state and local agencies to support a variety of enforcement, 
intervention, and prevention efforts to combat the methamphetamine 
problem. Finally, there was a variety of miscellaneous COPS grant 
programs. For example, the Regional Community Policing Initiative 
provided funds for training officers and representatives of communities 
and local governments, and COPS in Schools provided funds to law 
enforcement agencies to hire and train school resource officers to help 
prevent school violence and improve school and student safety.

Each year COPS was required to distribute half of the grant funds to 
agencies with populations exceeding 150,000 and half of the grant funds 
to agencies with populations of 150,000 or less.[Footnote 6]

Assessing whether COPS grants contributed to the decline in crime in 
the 1990s is complicated by many factors. Nationwide, the decline in 
crime began in 1993 before the COPS program made its first grants. 
Further, as crime declined during the 1990s, the amount of COPS grant 
funds increased. The general decline in crime makes it difficult to 
isolate the effect of COPS funds on crime.

COPS grants were distributed in ways that make rigorous evaluations of 
their causal impacts difficult to determine. For example, the majority 
of police agencies received at least one COPS grant, as we estimated 
that 75 percent of police agencies received some type of COPS grant in 
our study period and among larger agencies (i.e., those serving 
populations of 100,000 or more persons) over 90 percent received at 
least one COPS grant. This distribution of COPS grant recipient 
agencies limits the number of agencies that could be used as comparison 
agencies against which to assess the effects of COPS grant funds on the 
decline in crime. Further, within the COPS' program allowable limits on 
amounts of funds that agencies could request, agencies generally chose 
the amount of grant funds they wanted and they generally received the 
amount of COPS funds that they requested. This introduces potential 
selection bias into the analysis, in that agencies may have both self- 
selected themselves on whether to participate in the COPS program and 
on the extent to which they would participate. To assess the effects of 
the COPS grant, under conditions of selection bias, it is necessary to 
isolate the effects of the grants from an agency's underlying capacity 
to address crime problems in its community and its choice to 
participate in the COPS program.

To address these issues, we relied on methodological developments in 
research on crime that aim to disentangle the effects of programs such 
as COPS from other factors that could affect crime rates at the same 
time. For example, statistical models based on the use of a panel of 
data--or repeated observations on the same units, such as police 
agencies, over several time periods--allow for partial identification 
of the effects of COPS funds on crime by taking into account the 
variation between agencies over time in the amounts of expenditures and 
their relationships to crime rates. These methods also allow for the 
introduction of controls for pre-existing differences between units 
(agencies) and controls for differences over time that can help to 
identify causal relationships. In addition, crime research has adopted 
the use of statistical instruments as a method for identifying the 
causal direction of factors that could be determined simultaneously, 
such as the relationship between police officers and crime rates. 
Finally, by explicitly identifying mechanisms through which a program 
can have its effects--such as increases in officers attributable to 
COPS funds and their effects on crime--the program's model can be 
tested to rule out spurious correlations between inputs (such as COPS 
funds) and outcomes (such as crime).

Results: 

Of the $7.32 billion in total COPS grant funds obligated between 1994 
and 2001, the majority was obligated in the form of hiring grants, 
which accounted for about $4.69 billion, or 64 percent of all 
obligations. About 82 percent of agencies received at least one COPS 
grant, of any type, during this period, and about 75 percent received 
at least one hiring grant. By 2001, about 70 percent of the obligated 
amounts had been drawn down (or spent) by the agencies that received 
the grants.[Footnote 7] In the sample of COPS grantee agencies for 
which we obtained population and crime data and could make 
comparisons,[Footnote 8] we found that the COPS Office distributed 
grants according to statutory requirements--in that about half of the 
monies went to agencies covering populations of more than 150,000 and 
half went to agencies with populations of less than 150,000. In the 
aggregate, COPS grant funds were also distributed in proportion to the 
total volume of index crimes, but they were not distributed in 
proportion to the volume of violent crimes in the agencies that fell 
into these two population categories. For example, agencies serving 
populations of less than 150,000 persons received about 53 percent of 
COPS funding but they accounted for about 39 percent of violent crimes 
reported to the police. Agencies serving the smallest populations (such 
as places with populations of fewer than 25,000 persons) received an 
even larger share of COPS grant funds than the share of violent crimes 
that they contributed to the national total.

Our analysis of changes in policing tactics shows that COPS grant funds 
were associated with increases in police agencies' adoption of tactics 
that evaluations have shown to be effective in reducing crime. Our 
comparisons of the pre-COPS grant program (i.e., 1993) levels of four 
types of policing tactics with their levels during the COPS program 
(i.e., in 1997) in the Policing Strategies survey sample of police 
agencies showed firstly that among all police agencies there were 
increases in the adoption of problem-solving, place-oriented, community-
collaboration, and crime-analysis policing tactics. Specifically, among 
all agencies in the sample, between 1993 and 1997, the level of use of 
these tactics increased by about 32 percent--as measured by our 
summative index of policing tactics. However, our results also showed 
secondly that agencies that received COPS grant funds between 1993 and 
1997 increased their adoption of problem-solving and place-oriented 
tactics more than did the agencies that did not receive COPS grant 
funds during these years. For example, agencies that received COPS 
grant funds between 1993 and 1997 increased their level of problem-
solving tactics by 45 percent--as measured by our summative index of 
tactics--while those that did not receive grants increased them by 32 
percent. In addition, our analysis of changes in tactics during the 
COPS program in the National Evaluation of COPS survey data from 1996 
to 2000, also showed that COPS grantee agencies had larger increases in 
their use of problem-solving, place-oriented, and community-
collaboration tactics than did the agencies that had not received a 
COPS grant by 2000. Agencies that received a COPS grant before 1996 had 
the largest increases in place-oriented and community- collaboration 
tactics, while agencies that received a COPS grant between 1996 and 
2000 had larger increases in these tactics than did the agencies that 
had not received a COPS grant by 2000.

Our fixed-effects regression models of the effects of the variation in 
the timing and amount of COPS hiring grant expenditures on the levels 
of sworn officers over the years from 1990 to 2001 showed that COPS 
hiring grant expenditures were associated with increases in the net 
number of sworn police officers per capita. We obtained these results 
after controlling for agency-level differences in the timing and amount 
of other COPS grant expenditures and other federal law enforcement 
grant expenditures; after controlling for annual changes in local 
economic and demographic conditions in the county in which an agency 
was located; and after controlling for changes in state-level factors 
that could affect the level of sworn officers. Specifically, from our 
analyses of data for police agencies serving populations of 10,000 or 
more persons--which covered about 75 percent of the total population in 
the U.S.--we estimated that each $25,000 in COPS hiring grant 
expenditures per year was associated with a net increase in the stock 
of sworn officers of about six-tenths of a sworn officer. When we 
assessed the effects of COPS grant expenditures in specific years on 
the level of sworn officers in these years, we found that compared to 
the baseline, pre-COPS program year of 1993, COPS expenditures in 1998 
through 2000--three years in which COPS expenditures were at or near 
their peak amounts of about $815 million per year--were responsible for 
an estimated increase in the number of sworn officers per capita of 
about 3 percent above the levels that would have been expected without 
the funds. Upon projecting the results from our analysis of our sample 
of agencies to the entire U.S. population, we estimated that in the 
years from 1998 to 2000, COPS grant funds paid for about 18,000 
officers in each of these years.

Using COPS hiring grants as a statistical instrument to isolate the 
causal direction of the relationship between sworn officers and crime 
over the years from 1990 to 2001 in our sample of agencies serving 
populations of 10,000 or more persons, we found that COPS-funded 
increases in sworn officers per capita were associated with declines in 
the index crime rate and declines in the rates of murder, aggravated 
assault, robbery, burglary, larceny, and motor vehicle theft. From our 
regression results we calculated that a 1 percentage point increase in 
the level of COPS-funded sworn officers per capita was associated with 
about a 0.4 percent reduction in the index crime rate and about a 1 
percent reduction in the violent crime rate. Among types of violent 
crimes, the estimated effects of changes in officers on crime varied; 
for example, a 1 percent increase in the level of officers was 
associated with a 2 percent reduction in robbery rates but a 0.5 
percent reduction in the rate of aggravated assaults. These effects 
held after we controlled for the effects of other federal grant program 
funds received by agencies, local socio-economic and demographic 
changes that could affect crime, and state-level factors--such as 
increases in incarceration, changes in sentencing practice, and state- 
level changes in other programs such as welfare--that could also affect 
crime. In our analysis, the total effect of COPS grant expenditures on 
crime rates depended upon the level of COPS grant expenditures in a 
given year, and level of expenditures varied from year to year. For the 
years from 1998 through 2000--when COPS grant expenditures were at 
their peak levels--and among the agencies in our sample, we estimated 
that COPS grant expenditures were associated with about a 1 percent 
annual reduction in the index crime rate from its 1993 level, and about 
a 3 percent annual reduction in the violent crime rate from its 1993 
level. When we projected these results from the analysis of our sample 
to the entire U.S. population, we estimated the annual reduction in 
crimes attributable to COPS funds nationwide. For 1998--when COPS 
expenditures amounted to about $820 million or about 1.5 percent of all 
local law enforcement expenditures--we estimated that COPS grant 
expenditures were associated with a reduction of an about 212,000 index 
crimes and 68,000 violent crimes from their levels in 1993. These 
crimes due to COPS grant expenditures amounted to about 8 percent of 
the decline in index crimes between 1993 and 1998 and about 12 percent 
of the decline in violent crimes over this period. During the years 
1999 and 2000--when COPS expenditures also amounted to about $815 
million or 1.5 percent of all local law enforcement expenditures--and 
crime continued to decline, we calculated that the COPS-funded 
reductions in crimes accounted for about 5 percent of the total 
reduction in index crimes and about 9 percent of the total reduction in 
violent crimes from their 1993 levels.

Agency Comments: 

TO COME: 

If you or your staff have any questions concerning this report, please 
contact Laurie Ekstand at (202) or by e-m ail at Ekstrandl@gao.gov or 
William J. Sabol at (202) 512-3464 or Sabolwj@gao.gov. Key contributors 
to this report were: 

Sincerely yours,

Signed by: 

Laurie Ekstrand, Director: 
Homeland Security and Justice Issues: 

Signed by: 

Nancy Kingsbury: 
Managing Director, Applied Research and Methods: 

Enclosures - I: 

[End of section]

Enclosure I: Elements of the Database and Methods Used to Assess 
Effects of COPS Funds on Sworn Officers and Crime Rates: 

We constructed a database that consisted of up to 12 years of data 
(covering the period from 1990 to 2001) for each of 13,133 law 
enforcement agencies. These agencies represented about 75 percent of 
all local law enforcement agencies that reported data to the UCR; they 
covered about 95 percent of the population in the United States and 
about 95 percent of all crimes reported in the UCR. We constructed our 
database in the form of a panel, in which we obtained repeated measures 
on key variables in each agency over time.

The database contained information on federal grant amounts, crime, 
officers, and socio-economic and demographic factors associated with 
crime. The types of information contained in our database were: 

* Grant obligation amounts to and annual amounts expended by each 
recipient of a COPS grant;

* Annual amounts of other federal local law enforcement grants expended 
by both agencies that received COPS funds and those that did not;

* Annual data on the number of index crimes and each category of index 
crimes, along with annual data on the number of such crimes per 100,000 
population;

* Annual observations on the number of sworn police officers and the 
number of officers per 10,000 population;

* Annual data on economic and demographic factors that are related to 
crime, such as employment, per-capita income, relative size of persons 
in "crime-prone" age group of 15 to 24, the gender and racial 
composition of populations, and total population.

We linked data from the various sources to each law enforcement agency 
contained in our sample of agencies. The sources of data used to 
compile the annual observations from 1990 to 2001 on local police 
departments included: 

* FBI Uniform Crime Reports (UCR)--Annual data files on the number of 
crimes and sworn officers reported by each agency to the UCR. The crime 
data are available separately for each Index Crime, which include the 
crimes of murder and non-negligent manslaughter, rape, robbery, 
aggravated assault, burglary, larceny, and motor vehicle theft. In 
addition, the data on sworn officers represent the number of officers 
in each agency on October 31 of each year. We used the originating 
agency code (or ORI) variable and census place codes to link crime and 
officer data to other data sources.

* COPS Office--Annual data on each grant awarded and amounts obligated 
for each grant. The COPS data include the ORI code and other 
information that we used to link with other data sources.

* Office of Justice Programs Financial Data--Annual data on the amount 
drawn down from each grant awarded by OJP. Because OJP and COPS share 
data, these OJP data also included COPS grant draw downs. The data on 
draw downs of funds best represent expenditures of federal grant monies 
in the years in which the dollars were spent. By contrast, amounts 
obligated in a given year may not be spent in that year. We used 
information about Census place (FIPS) codes and about OJP vendors to 
link data.

* Bureau of Economic Analysis--County level data on per capita income 
and employment. We linked these data to agency-level data using census 
place codes. Local economic conditions within each county are applied 
to each agency within a county.

* Census of Population Intercensal Estimates--Annual data for each 
county from 1990 to 1999 on population totals, and population 
breakdowns by gender, race, and age. We linked these data using census 
place code identifiers, and we extrapolated from underlying trends in 
each population category to obtain estimates for 2000 and 2001.

In addition to the sources above that provided annual data on local 
policing agencies, we obtained and included in our database information 
from two separate surveys of nationally representative samples of local 
law enforcement agencies about the types of policing tactics that they 
implemented. Both surveys consisted of two waves of observations on the 
same police departments. The first survey, the National Survey of 
Community Policing Strategies (or "Policing Strategies Survey"), was 
conducted by the Police Foundation in 1993 (pre COPS), and Opinion 
Research Corporation (ORC) Macro International, Inc., and the Police 
Executive Research Forum (or PERF) in 1997 (during the COPS program). 
We used the Policing Strategies Survey data that contain information on 
1,242 police agencies that responded to both waves of the survey, and 
of these, we were able to link the data from 1,236 agencies to our 
larger database on crime, officers, monies, and economic conditions. We 
used the Policing Strategies Survey data to compare changes in the 
types and levels of policing tactics that occurred during the COPS 
program with pre-COPS levels of tactics.

The second survey, the National Evaluation of the COPS Program (or 
"National Evaluation of COPS"), was conducted by the Urban Institute, 
and it consisted of two waves of observations on a sample of 1,225 
agencies in 1996 and again in 2000. We used the data from this survey 
to compare changes in policing occurring during the period of the COPS 
program. We were able to link the data from these two sources to our 
larger database using various identifiers.

Prior to developing our database, we assessed the reliability of each 
data source and in preparing this report, we used only the data that we 
found to be sufficiently reliable for the purposes of our report.

Methods Used in Our Analyses: 

We used various methods to analyze each of our reporting objectives.

Methods to Analyze the Flow of COPS Funds: 

To assess the flow of COPS funds, we use the OJP Financial data to 
compute the amount of COPS funds obligated by COPS grants and the 
amount expended--or drawn down--by local police agencies during the 
period from 1994 to 2001. To describe the overall COPS funding trends 
by grant type, we analyzed the universe of agencies in the OJP data 
that received any federal law enforcement grant during the period 1990- 
2001, regardless of whether or not the agency received a COPS grant 
during the period. For analyses of COPS funds by agency population 
sizes and for comparisons of funding levels with levels of violent and 
total index crime, we limited our analysis to the subsample of agencies 
whose crime and population data we were able to link to the OJP data. 
This resulted in a sample of 11,187 agencies--or 85 percent--of the 
13,133 agencies in our crime sample. These agencies accounted for 86 
percent of the reported index crimes in the U.S. (between 1990 and 
2001). We capture the vast majority of COPS funds, but we exclude some 
COPS funds from our analyses either because we could not match them to 
agencies that reported data to the UCR or because the funds went to 
agencies that we excluded from our analyses.[Footnote 9]

In analyzing the flow of COPS funds to local law enforcement agencies, 
our objectives were to assess whether the COPS grants were distributed 
according to statutory requirements and to assess the effect of these 
requirements on the distribution of COPS funds in relation to the 
volume of serious crimes occurring in the agencies that received COPS 
grants.

Methods to Analyze Changes in Policing Practices and Tactics: 

To address whether COPS grants were associated with increases in the 
adoption of crime-preventing policing tactics, we analyzed the Policing 
Strategies and National Evaluation of COPS survey data. We compared 
differences in the levels of tactics between agencies that received 
COPS grants and those that did not receive grants during the two 
periods covered by the surveys. With the Policing Strategies Survey, we 
compared pre-and post-COPS program differences in the adoption of 
tactics (or from 1993 to 1997), and with the National Evaluation of 
COPS Survey, we compared changes in the adoption of tactics that 
occurred within the COPS program (or from 1996 to 2000).

Each of the surveys reported data on the policing tactics used by 
agencies. Survey responses were obtained from knowledgeable officials 
within each agency, such as the police chief or the chief's designee. 
The number of items related to policing tactics differed between the 
two surveys. For the data in each survey, we classified items into 
tactics categories based on our assessment of the policing literature. 
We then assessed statistically the degree to which the items that we 
included in each of our four categories were correlated with each other 
and uncorrelated with items in the other categories.

The Policing Strategies Survey data contained 30 items related to 
policing tactics. We combined eight tactics pertaining to increasing 
officer contact with citizens and improving citizen feedback into a 
community collaboration index. We used items on the crime analysis 
units within police departments to create our index of crime analysis. 
We combined seven tactics pertaining to increasing enforcement activity 
or place management in buildings, neighborhoods, or other specific 
places into an index of place-focused tactics. And we compiled the data 
on twelve items that reflected organizational efforts to reduce or 
interrupt recurring mechanisms that may encourage crime into a problem- 
solving tactics index. The classification of items from the Policing 
Strategies Survey into our four indexes of types of policing tactics is 
shown in table 2.

Table 1: Policing Tactics and Strategy Items Utilized to Create 
Summative Indexes in the Policing Strategies Survey.

Community collaboration: 

* Agency uses foot patrol as a specific assignment; 
* Agency uses foot patrol as a periodic expectation for officers 
assigned to cars; 
* Agency uses citizen surveys to determine community needs and 
priorities; 
* Agency uses citizen surveys to evaluate police service; 
* Patrol officers conduct surveys in area of assignment; 
* Patrol officer meet regularly with community groups; 
* Supervisors maintain regular contact with community leaders; 
* Agency uses citizens as volunteers within the police agency.

Crime analysis: 

* Agency has a decentralized crime analysis unit/ function; 
* Agency has a centralized crime analysis unit/function; 
* Supervisors manage crime analysis for geographic area of 
responsibility.

Place-oriented practices: 

* Agency designates some officers as "community" or "neighborhood" 
officers; 
* Agency uses building code enforcement as a means of helping remove 
crime; 
* Geographically based crime analysis made available to officers; 
* Command or decision-making responsibility tied to neighborhoods or 
beats; 
* Patrol officers enforce civil and code violations in area; 
* Fixed assignment of patrol officers to specific beats or areas; 
* Agency uses other regulatory codes to combat drugs and crime. 

Problem-solving practices: 

* Specific training provided officers for problem identification and 
resolution; 
* Training for citizens in problem identification or resolution; 
* Landlord/manager training programs for order maintenance; 
* Interagency involvement in problem identification and resolution; 
* Agency has revised procedures to deal with neighborhood problems; 
* Multidisciplinary teams to deal with special problems such as child; 
* Specialized problem solving unit; 
* Patrol officers work with citizens to identify and resolve area 
problems; 
* Organization has been redesigned to support problem solving efforts; 
* Line supervisors make final decision about which problems are to be 
addressed; 
* Line supervisors make final decision about how to handle most 
community problems; 
* Line supervisors make final decision about application of agency 
resources to solve problem in geographic area of responsibility.

Source: Policing Strategies Survey, 1993 and 1997.

Note: Each individual items is coded dichotomously (yes/no) to indicate 
whether an agency implemented the specific tactic.

[End of table]

The National Evaluation of COPS Survey contained data on 19 items 
relating to policing tactics. We classified these items into the same 
tactics categories as we did with the Policing Strategies Survey data. 
Many of the items in the National Evaluation of COPS Survey were worded 
in the same way as in the Policing Strategies Survey.

Table 2: Policing Tactics and Strategy Items Utilized to Create 
Summative Indexes in the National Evaluation of COPS Survey.

Community collaboration: 

* Regular community meetings to discuss crime; 
* Surveys of citizens to determine general community needs and 
satisfaction with your agency; 
* Citizen action/advisory councils in precincts or beats; 
* Officers analyze community resident's comments to identify recurring 
patterns of crime and disorder on their beats; 
* Considering neighborhood values in creating solutions or planning 
projects; 
* Varying styles of preventive patrol (e.g. bikes, walk and talk); 
* Joint projects with local businesses to reduce disorder or petty 
crime. 

Crime analysis: 

* Analyzing crime patterns using computerized geographic information 
systems; 
* Officers analyze and use crime data to identify recurring patterns of 
crime and disorder on their beats. 

Place-oriented practices: 

* Clean up/fix up projects with community residents; 
* Joint projects with community residents to reduce disorder such as 
loitering, public drinking; 
* Beat or patrol boundaries that coincide with neighborhood/community 
boundaries; 
* Alcohol, housing, or other code enforcement to combat crime and 
disorder. 

Problem-solving practices: 

* Designating certain patterns as "problems" or "projects" requiring 
non-traditional responses; 
* Analyzing problems with business or property owners, school 
principals, or property managers or occupants; 
* Analyzing problems with probation/parole officers or others who 
monitor offenders; 
* Using agency data to measure effects of responses to problems; 
* Documenting problems, projects, analyses, responses, failures, and 
successes in writing; 
* Team approach instead of chain of command for prevention, problem 
solving, and law enforcement.

Source: National Evaluation of COPS Survey, 1996 and 2000.

Note: Each individual items is coded dichotomously (yes/no) to indicate 
whether an agency implemented the specific tactic.

[End of table]

From each of the surveys, we developed summative indexes of the overall 
number tactics and the number of tactics within each of the 4 
categories of policing tactics. We then computed and compared changes 
in the mean levels of tactics between the COPS grantee and non-grantee 
agencies. To control for differences between agencies and trends over 
time in the adoption of policing tactics that could account for 
differences in tactics, in our analysis of the Policing Strategies 
Survey data and the National Evaluation of COPS Survey data, we 
estimated regressions that controlled for social and economic 
characteristics of the places in which police agencies were located and 
pre-existing trends in officers and crimes.

Methods to Estimate the Effects of COPS Funds on Officers and Crime: 

We adopted similar approaches to estimating the effects of COPS funds 
on officers and crime, as described below.

Methods to Estimate the Effects of COPS Funds on Officers: 

To estimate the effect of COPS funds on officers, we used fixed-effects 
regression methods that permitted us to assess changes in the levels of 
sworn officers per 10,000 persons as a function of COPS funds, other 
federal funds, local economic conditions, and changes in the age, 
gender, and racial composition of local populations. The fixed effects 
regression models allow us to control for two sources of unmeasured 
variation (i.e., omitted variables): The pre-existing differences among 
the agencies in our sample that are constant within agencies over time 
and the differences within agencies over time in relation to the 
overall trends in variables. By adopting these models we are able to 
control for the effects of unmeasured variables that vary over time 
between agencies and that might be correlated with our dependent 
variables. We introduced fixed effects at the level of the local law 
enforcement agency. In addition, to control for state-level influences 
on officers that we were unable to observe directly--such as changes in 
state sentencing practices--we also introduced into our models state- 
by-year level fixed effects.

Finally, to control for underlying trends in the pre-COPS grant period 
in sworn officers and crime, we estimated regressions that analyzed 
these trends, and then we classified each agency's trend within 
population size groups. This allowed us to compare agencies within size 
categories that had similar trends in officers and crime prior to the 
COPS program. Specifically, we separated the agencies in 4 groups based 
on the growth rate in both officers and in crime during 1990-1993, 
which is prior to the implementation of the COPS program. We 
constructed each combination of these groups, which produced 16 cells. 
These cells were then interacted with each year, and 4 population 
categories, for a total of 704 effects. In essence then, each agency is 
being compared with another agency that had a similar "trajectory" of 
crime and officers in the pre-COPS period.[Footnote 10]

We analyzed the data for 5,199 police agencies with populations of 
10,000 or more persons. We estimated several regressions of the effect 
of COPS funds on sworn officers, and we included as time-varying 
independent variables the per capita amounts of COPS hiring grants, 
COPS innovative grants, COPS MORE grants, COPS miscellaneous grants, 
Edward Byrne Memorial State and Local Law Enforcement Assistance 
Discretionary Grants, Local Law Enforcement Block Grants (LLEBG), the 
employment to population ratio, per capita income, the percent of the 
population that was male, the percent of the population that was 
nonwhite, and the percent of the population that was between the ages 
of 15 and 24. All of our economic and population measures were observed 
at the level of the county that contained the local law enforcement 
agency. Our regressions included the agency level fixed effects, year 
effects, effects for the pre-COPS trends in the growth of officers and 
crime, population weights (to allow us to estimate national-level 
effects), and state-by-year fixed effects.

Methods to Estimate the Effects of COPS Funds on Crime through 
Officers: 

We estimated the impact of COPS funding on crime through these funds' 
effects on changes in officers. We made use of the fact that, unlike 
the other COPS grant types, hiring grants were earmarked specifically 
for the hiring of officers. Consequently, variation in the number of 
officers coming from hiring grant should be unrelated with other 
changes in police expenditures. In this sense, we used COPS hiring as 
an instrument to isolate the direction of causality between officers 
and crime rates.

We then estimated population-weighted regressions of the impact of the 
flow of COPS dollars on crime rates, net of pre-existing trends in 
crime rates and growth of officers, and net of economic conditions, 
population change, and other amounts of funding for local law 
enforcement. We used the population weights to allow us to develop 
estimates for the nation as a whole. We estimated our regressions on 
the same sample of 5,199 agencies with populations of 10,000 or more 
that we used in our officers equations. We estimated crime equations 
separately by type of crime and population size group. Under the 
assumption that hiring grants can be used as an instrument, we used the 
results from the two regressions--officer rate on COPS funds and crime 
rate on COPS funds--to calculate the elasticity of crime with respect 
to officers (i.e., percent change in crime rates attributable to the 
percent change in officers).

More specifically, we estimated the effect of COPS funds on crime using 
a reduced form equation that included measures of specific types of 
COPS grant funds (e.g., hiring, MORE, innovative, and miscellaneous 
grants) expended, measures of other federal grant funds expended, and 
the controls for socio-economic and demographic changes in the 
population. We included the 704 variables that controlled for pre-COPS 
trends in officers and crime, and we introduced agency level, year 
level, and state-by-year fixed effects. The state-by-year fixed effects 
allow us to control for unmeasured state-level sources of variation 
with crime, such as increases in state incarceration rates, changes in 
state sentencing practices, and changes in other state programs--such 
as welfare reform--that could affect crime rates. We estimated 
regressions separately for the index crime rate and by type of index 
crime.

After obtaining the coefficients from our officers and crime 
regressions, and to obtain estimates of the effects of COPS funds on 
crime through officers, we then calculated the elasticity of crime with 
respect to officers in any given year. The elasticity of crime with 
respect to officers provides an estimate of the effect of a 1 percent 
change in the level of sworn officers per capita on the per capita 
crime rate. Using these elasticities, we then apportioned the amount of 
the reduction in crime that we could attribute to COPS funds. To 
project the effects of COPS funds on crime to the nation as a whole, we 
then weighted the estimates of COPS effects on crime in our sample up 
to the nation as whole.

[End of section]

FOOTNOTES

[1] VCCLEA contained other provisions to address violent crime, such 
encouraging states to increase the use of incarceration for violent 
offenders through the Violent Offender Initiative and Truth-in- 
Sentencing grants, enhancing penalties for gang crimes, and expanding 
the number of Federal death penalty offenses.

[2] The study that we reviewed was: Zhao, J. and Thurman, Q. A National 
Evaluation of the Effect of COPS Grants on Crime from 1994 to 1999 
(December 2001). Our review of this study was reported in: GAO: 
Technical Assessment of Zhao and Thurman's 2001 Evaluation of the 
Effects of COPS Grants on Crime, GAO-03-867R (Washington, D.C.: June 
13, 2003).

[3] In addition to the Zhao and Thurman work cited above, David 
Muhlhausen has assessed the effects of COPS funds on crime rates. Using 
county-level data on crimes and funds, Muhlhausen found that other than 
the Innovative grant program, COPS grants were not associated with 
reductions in crime. See: Muhlhausen, D. Do Community Oriented Policing 
Services Grants Affect Violent Crime Rates (Washington, D.C.: Heritage 
Foundation, May 25, 2001). 

[4] The first survey was National Survey of Community Policing 
Strategies, and it was conducted by the Police Foundation in 1993 to 
provide information in what was occurring and what needed to occur in 
the development and implementation of community policing. In 1997, 
Opinion Research Corporation (ORC) Macro International, Inc., and the 
Police Executive Research Forum (PERF) conducted the National Survey of 
Community Policing Strategies Update, a longitudinal follow-up to the 
previous survey, using the same sample as the 1993 survey. The 1997 
survey was designed to provide information on the most current 
practices and trends in community policing. In the remainder of this 
letter, we refer to the two waves of this longitudinal survey as the 
Policing Strategies survey. The second survey was the National 
Evaluation of the COPS Program survey, which was conducted by the Urban 
Institute between 1996 and 2000. It was a nationally-representative 
sample of law enforcement agencies that were contacted in 1996 and 
again in 2000. In the remainder of this letter, we refer to this second 
survey as the National Evaluation of COPS survey. 

[5] MORE grants in 1995 could also be used to pay for police officer 
overtime costs. 

[6] Of funds available in any fiscal year, up to 3 percent may be used 
for technical assistance or for evaluations or studies carried out or 
commissioned by the Attorney General. The requirement to allocate the 
funds by size of agency population applies to the remaining funds in 
any fiscal year (USC 42, chapter 46, subchapter XX, sec. 3793, (a) (11) 
(B). 

[7] Due to lags between the time when grants are obligated and all of 
the funds are expended, not all COPS obligated amounts during the years 
from 1994 to 2001 were drawn down or expended in that same period by 
the agencies that received the grants. 

[8] This sample consisted of 11,187 agencies, or 85 percent of the 
agencies that reported crime data to the UCR. This group of agencies 
accounted for 86 percent of the reported index crimes in the United 
states between 1990 and 2001. 

[9] The COPS Office received applications from law enforcement agencies 
that did not have originating agency (ORI) numbers. These numbers are 
used by the UCR to identify agencies that report crimes. The COPS 
Office assigned the agencies that did not have ORIs a "ZZ" ORI code. 
This code was based upon a number that the applicant agency reported to 
which the COPS Office appended a "ZZ" code. We were unable to match 
these "ZZ" agencies to agencies in the UCR. However, our analysis of 
these agencies suggests that they were mostly smaller agencies of 
recent origin as well as consortia, tribal and private research 
organizations. 

[10] This approach was first implemented by Evans, W. and Owens, E in 
Flypaper COPS (College Park, Md.: Univeristy of Maryland, April, 2005).