During the very brief Reich level, Pavel fires his gun in the middle of a large crowd, forcing you to run for your life (or freedom at least). Just sprint the entire time and make sure you don't miss the jump between the two sets of scaffolding and you should be fine.
Check out the video below for a full playthrough of the game showing all collectibles, miscellaneous achievements like this one, and the Moral Points I obtained (I skipped a lot of them) in order to get the Redemption achievement. The Reich mission starts at timestamp
12:55.