Why Did Kirschner Reveal Price's Alleged Drug Use?

During yesterday’s hearing to lift the pretrial restrictions, US Attorney Glen Kirschner revealed that defendant Joe Price had either possessed and/or distributed crystal methamphetamine, cocaine and Ecstasy.  

What was the significance of revealing this information now?  While the Defense was winning their argument that the Defendants are not a flight risk, this tidbit of information clearly didn’t tie into the government’s argument that they need pre-trial restrictions because they have money to flee.  So why do it?  
Weisberg said the defendants had been cooperating with authorities, and Kirschner used the information to single out that Price was not cooperating.  Was Kirschner using it to rattle the defense, and show that Price lied on his application at DC Pre-Trial Services. Establishing that Price is liar is strong step toward an establishing that the Defendant could obstruct justice.