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How do you count gang members?

Police officers use field interview cards to identify gang members

Gang membership has risen by 25 percent nationally, according to a Monday article in USA Today. * The latest tally from the Justice Department found there were more than 1 million gang members in the United States as of 2008, up from 800,000 in 2005. How do you count gang members?

Start with a field interview card. At the street level, whenever a police officer stops someone for suspicious behavior, the reason is documented on an “FI” card, which includes the person’s name, age, and other identifying information. If the officer suspects gang affiliation because of someone’s attire, tattoos, knowledge of gang signs, and so forth, a note to that effect is added to the card. (The rules on what counts as legitimate evidence vary by state or police agency.) A supervisor typically reviews the field interview card and decides whether the person meets the threshold before recording him or her as a “gang member” in the local database.

Identifying gang members on the street can be difficult, especially given that the definition of a “gang” is itself in question. (The new report considers a gang to be “a group or association of three or more persons” who “engage in criminal activity that creates an atmosphere of fear and intimidation.”) Not every potential gang member must fit every criterion to be designated as such. In South Central Los Angeles, for example, an officer will look for any two of eight possible factors, including whether the person associates with known gang members and whether he appears to know gang signs and language. (One doesn’t need to commit a crime in order to be counted, but it helps.) In Portland, Ore., officers look for either one hard and fast indicator—if someone states outright that he’s in a gang, that’s enough—or two likely indicators, such as a demonstrated willingness to commit a crime and a style of clothing associated with gangs. Someone who has a gang designation report filed under his name can always dispute it in court.

By contrast, keeping track of prison gang statistics is fairly straightforward. For one, inmates are a captive audience. Officers try to determine whether someone is a gang member from the moment he or she hits the reception area. Interviews are conducted and tattoos are photographed. According to the new report, about 16 percent of all gang members are incarcerated.

To come up with the national numbers, the Department of Justice sends out a survey to local and state law enforcement agencies and asks them to indicate an estimated range of gang members in their districts, such as “100-250” or “251-500.” These numbers are combined with those from gang-related criminal investigations and prison stats in order to produce a national estimate.

There are a couple of reasons why the totals might be a little off. Not only do state and local law enforcement agencies use different criteria for identifying gang members, but the number of agencies that report their data also varies from year to year. In 2005, for example, only 455 state and local law enforcement agencies participated in the survey. In the most recent version, 3,052 sent in their numbers.

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Explainer thanks Joel Best of the University of Delaware; Sgt. Walt Frazier of the Reno Police Department; Sgt. Brian Gallagher of LAPD’s 77th Division Gang Unit; Lt. Dave Hendrie of the Portland, Ore., Gang Enforcement Team; Tim Thrasher of the Washington Department of Corrections; and Capt. Anthony Williams of the Richmond, Calif., Police Department.

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Correction, Nov. 4, 2010: This article originally described the government tally as having been released on Monday. The numbers were first published in 2009. (Return to the corrected sentence.)