To clarify for anyone reading, "Overwatch" is not referring to the Blizzard game, but an in-game Counterstrike tool in which players review recorded gameplay of a suspected cheater.

When enough reviewers agree that a player is cheating, that person is banned. Each player has a hidden successful conviction rating and on occasion the system will send you professional players or non-cheating players in an effort to verify your ability.

This is only meant to convict the most blatant of cheaters. It's fairly successful for what it's intended to do, but of course, it does not even remotely catch every cheater.