I once heard, and this is not confirmed, that LAPD had to drop its standards because it was not getting enough applicants that were qualified and they now allow you to be convicted of one misdemeanor drug charge and still be eligible. It may be possible that is how your buddy became a cop. He was not arrested but they may have decided to look passed the drug use.
We have some people here from the LA area that may be able to answer more accurately...
"Knowing what you stand for limits what you fall for"
"Hey, I don't know everything just because I'm a CJ student...I know everything because I'm a female." -PathosLogos