I just finished reading your novel Deception and enjoyed it. However, I question whether the police officers in the book who have backgrounds in gang activity, including Ollie’s partner Manny, would be allowed to join the police force. From my experience, the extensive investigation into a potential officer's background allows for only a completely pristine past.
Thanks for your thoughtful note about Deception.
It’s true that those with gang and other criminal backgrounds who wish to become cops go through a lot of screening and probation and often outright rejection, but in fact a number of ex-gang members do become cops, including gang specialists.
Of course, some police departments may have rules absolutely forbidding this from happening, but others do not. Fortunately for Manny, his police department is one that permits former gang members, after long scrutiny, to become police. The inside knowledge they have, and their rapport with gang members and savvy to not be fooled by them, can be used to great advantage.
For more information on this subject, see Randy Alcorn’s book Deception.