Looking for a short story about an man who lives in a society where instead of executing criminals, the government erases their minds and turns them into new people. The protagonist is a normal law-abiding citizen (well, now here is) with a normal 9-5 job, who spends practically all his free time trying to find out who he was before being erased.
At one point he has a flashback-like hit-the-deck reaction to a nearby vehicle backfiring, after which his previous personality starts to manifest as a voice in his head.
At the end of the story, after discovering that he had been a master assassin who was caught trying to kill the President of the United States, he decides that he return to being an assassin for hire, but will maintain his previous post-erasure lifestyle with the addition of the occasional random murder.