Not sure I like the phrase 'self righteous'. With it's negative connotation you could be starting off with a hero nobody likes. That's okay in a script but in a logline it can be troublesome. It almost makes me want the sister to be the protag. Also you might want to give the guy more of a connection to the program: When the government's secret plan to kill junkies with mutant insects projects a DEA administrator's 'casual use' sister as 'acceptable collateral damage' he takes on a swarm of self righteous DEA agents.
Suggested titles:
Buzz Kill
CounteRAID (winner of the product placement award)
Swarm to Protect