By Luc Cohen NEW YORK (Reuters) – A former top Mexican law enforcement official convicted earlier this year on US charges that he took millions of dollars in bribes from drug traffickers is seeking a new trial, arguing he has come across evidence key witnesses lied on the stand. Lawyers for Genaro Garcia Luna, who as public security minister from 2006-2012 led the country’s fight against drug cartels, said in a court filing on Friday that they had also found evidence that prosecutors’ cooperating witnesses had improperly communicated with each other before trial. “Mr. Garcia Luna was convicted…