The survey is sent to a wide variety of law enforcement agencies from throughout the country. The following information comes from the Bureau of Justice's website (see the link below):
2002–Present NYGS Sample (Current Sample):
- All police departments serving cities with populations of 50,000 or more (n=624).
- All suburban county police and sheriffs’ departments (n=739).
- A randomly selected sample of police departments serving cities with populations between 2,500 and 49,999 (n=543).
- A randomly selected sample of rural county police and sheriffs’ departments (n=492).
Hereafter, larger cities refers to cities with populations of 50,000 or more, and smaller cities refers to cities with populations between 2,500 and 49,999. Finally, study population refers to the entire group of jurisdictions that the current sample represents; that is, all jurisdictions served by county law enforcement agencies and all jurisdictions with populations of 2,500 or more served by city (e.g., municipal) police departments.
I hope this helps you.
The National Youth Gang Center (NYGC) since 1996 has been conducting yearly surveys which involve law enforcement agencies. These are meant to determine the presence of local gangs, their characteristics and how they behave. This helps in understanding the problems posed by local gangs in different jurisdictions all over the United States.
For the National Youth Gang Survey (NYGS) a sample representing law enforcement agencies serving areas from large urban cities to small rural counties is enquired about how active gangs are, how their size has changed, if there has been any increase in the number of gangs, the number of crimes committed by the gangs and other similar questions. The results from the surveys are collated and analyzed to better understand the problem and think of ways to tackle it.