The National Archive of Criminal Justice Data (NACJD) contains actual data sets from various surveys and makes them available for download and further manipulation by researchers. Over 500 data sets are currently held in the archive with most being publicly available and others available only to researchers affiliated with the Inter‐university Consortium for Political and Social Research (ICPSR). The archive itself was established in 1978 by the ICPSR and the Bureau of Justice Statistics (BJS). The mission of the NACJD “is to facilitate and encourage research in the field of criminal justice through the preservation and sharing of data resources, and the provision of specialized training in quantitative analysis of crime and justice data.”
Information about the data sets can be browsed by title, principal investigator’s name, study number, or subject. Subjects include attitude surveys, community studies, corrections, court case processing, courts, criminal justice system, crime and delinquency, official statistics, police, victimization, and drugs, alcohol, and crime. Also browsable are lists of recent additions to the archive, recent updates to previous surveys, the most popular studies, and forthcoming additions and updates. The most recent update to the archives was added only a week prior to the writing of this review and the next most recent addition only three weeks prior. This frequent updating demonstrates the archive is not static but is consistently being enhanced with new material.
Browsing through the subject divisions of the data sets is informative though it is not always clear why some data sets were assigned to certain subjects and not others. The user should be aware that the subject divisions are useful as a convenience but if a desired study is not located by browsing under the most likely subject heading, be sure to browse other subject headings or use the search function.
One can search for a study by the investigator’s name or by keywords in the title or abstract. Search terms are not case sensitive. Search strings enclosed in quotes are interpreted as single search terms while unquoted strings of multiple words are automatically joined with an AND by the search engine.
Not attempting to be exhaustive, a few examples of the type of material found in the archive should suffice. Attitude surveys come mostly from the 1970s and 1980s, with a few from the early 1990s. They contain reviews of attitudes on drugs, crime, abortion, violence, lawyers, sex discrimination, race relations, and the like. Community studies cover crime in Atlanta, Chicago, Minneapolis/St. Paul, Detroit, New York, Los Angeles, and some smaller communities. Corrections surveys include those on capital punishment, census data on correctional facilities, differential effects of various correctional treatments, gender of prisoners, career criminals, recidivism, correctional officers, and more. Court case processing data sets include surveys of court records from various locations in the US, both civil and criminal, local and nationwide. Court data sets include surveys on effects of sentencing reforms, surveys of judges and prosecutors on various topics, and the public image of courts. Criminal justice system data sets include expenditure and employment data, arrest rates, crime rates, repeat offender laws, and so forth.
Abstracts of the studies are always available online. The abstracts are detailed and describe what information was surveyed in the study, how the data were gathered, and in what format the data are available. Documentation and code books are usually accessible online for the data sets though some are available only in paper format.
To link to the actual data for publicly available files, the user is required to give an email address. Data may then be downloaded in either compressed or uncompressed format. GZIP is the compression software used at the site and “unzipping” software is available for download. This is not a site that allows the user to search for statistics instantly online. It is meant to be used by social science researchers who want to download and manipulate large data sets. Since no manipulation or direct viewing of the online data is possible at this site, this is not a location suitable for casual users or those needing just a quick statistic or two. However, for the serious social researcher interested in acquisition and statistical manipulation of large data sets, this is a wonderful resource.
There are a some related sites on the Internet that may also be of interest to these researchers:
Crime & Justice Electronic Data Abstracts at <http://www.ojp.usdoj.gov/bjs/dtdata. htm> has similar information and the files are also compressed and downloadable in spreadsheet format. United Nations Surveys of Crime Trends and Operations of Criminal Justice Systems at <http://www.ifs.univie.ac. at/uncjin/mosaic/wcs.html> contains worldwide information while the other sites noted here are limited to US data. Files here are also compressed and may be downloaded in spreadsheet or SPSS data formats.
The General Social Survey (GSS) at <http://gort.ucsd.edu/gss/> or <http://www. icpsr.umich.edu/gss/> is a bit different in that at either of these sites the GSS can be manipulated statistically online and need not be downloaded. This makes it somewhat more convenient to use although processing time can be a bit lengthy. Finally, the Sourcebook of Criminal Justice Statistics Online at <http://www.albany.edu/sourcebook/> is a version of the classic resource of criminal justice statistics presented here in Adobe Acrobat format online. It can be searched by keyword or browsed via the index of subjects. For those needing to find a statistic in criminal justice quickly, this is the place to begin. For serious researchers interested in statistical manipulation of large data sets, the other sites, including NACJD are more suitable.
