1. Signs, Symbols & Graffiti
Gangs
Signs, Symbols & Graffiti

2. Colors
Gang colors have traditionally been shown with bandanas. This practice began in the California prisons, where inmates were issued a bandana as part of their clothing.
Bandanas are treated as a flag by gang members, and are often given the same reverence that is given the American flag. Burning a rival gang member’s bandana is an ultimate act of disrespect.
A bandana that is carefully folded (and possibly pressed with an iron) is a strong indicator of gang association, whereas a bandana crumpled in a back pocket is not.

3. Colors
Bloods – Red
Crips – Blue
Latin Kings – Gold
MS-13 – Blue/Black

4. Clothing
Colors in other clothing may also indicate gang membership. In the 1980s and 1990s, it was common to see gang members literally head-to-toe in red or blue. This is far less common in 2009, when many gang members have gone “low pro” (low profile) to avoid the attention of law enforcement.

5. Clothing
Colored clothing commonly used by gangs includes web belts, shoes, shoe laces, and ball caps. Manufacturers aid gangs by producing clothing in color combinations that gangs desire, going so far as producing professional sports team attire in non-team colors such as New York Yankees hats in black and yellow (for the Latin Kings).

6. Numbers
All street gangs and many gang-like groups associate with certain numbers or use numbers to communicate with other gangs or groups. Numbers may have significance such as the location where the gang formed. Numbers may be associated with the Nation allegiance of a gang. Numbers may also represent the letters of the alphabet — a practice of nearly all street gangs and gang-like groups.
5 People Nation, Bloods
360 Latin Kings
666 Neo-Nazi groups
XIII – MS-13
6 – Crips
187 Murder / death threat (all gangs)

7. Hand Symbols
Hand signals are used by gangs as a means of communicating gang affiliation and/or as a challenge to rival gang members, called “throwing signs.”  These signals or signs are made by forming letters or numbers with the hands and fingers, depicting the gang symbol or initials.  By using these signals, the gang member can show to which gang he belongs and issue challenges to other gangs in the vicinity.
"Throwing up" a gang sign with the hands is one of the most known and obvious forms of "claiming." It is used in many situations where other identifiers may not be possible or appropriate, and can also show that a gang member is in the area to "do business" as opposed to just passing through.
Bloods

8. Graffiti
If graffiti consists of bubble script and uses more than a single color of paint, it is most likely not gang-related. Consider strikingly angular letters, which are painted in one color and often combined with satanic or religious images, as probably gang-related.
Latin Kings

9. Graffiti
Numbers have meaning too. Sometimes the number stands for the letter in the alphabet and the location of the gang.
Three digit numbers, 031 or 021 identifies the bloods.
Two digit numbers like 13 & 14 signify a Hispanic gang.
187 = kill

10. Graffiti
Note that two numbers preceded by N, S, E or W (north, south, east or west), represent directions or the gang's territorial orientation.
Consider that an "S" that follows N, S, E or W typically means "side."
"WS18" = West Side 18th Street gang, which is based in California.

11. Graffiti
Interpret graffiti with crossed out letters or a series of numbers followed by a "K," which stands for kill, as a threat from a rival gang towards the gang specified in the graffiti.

12. Symbols Gangs can also be identified through symbols.
Bloods – 5 point star
Crips – 6 point crown with star
Latin Kings – 5 point crown
MS-15 – Devils horn/MSXIII
Aryan Brotherhood – swastika/shamrock clover