No one likes a cheater, and Valve is giving "Counter-Strike: Global Offensive" players the ability to govern themselves as part of the Overwatch program, which turns select players into official "investigators" with a watchful eye over the community.
Overwatch Investigators will be chosen based on their activity within Counter-Strike: GO. According to the official Overwatch FAQ, competitive wins, account age, hours played, skill level and low report count are all stats that will effect whether or not a player is selected as an Overwatch Investigator.
If a player is deputized by Valve, an Overwatch icon will appear on the Counter-Strike: GO main menu, letting them know that a case needs their evaluation. Should that player choose to participate, they will be presented with a 10-minute replay of “the suspect” playing a match. Because player names have been changed and in-game chat and audio have been removed, Investigators will have to base their judgment of the accused player solely on their actions in-game. If all of the Investigators on a case believe the player has committed an offense a ban can be issued based on the severity of that player's actions.
The Overwatch program is currently in beta, with Valve adding test cases to help ensure that everything runs and operates correctly. The plan is to eventually let the community take full control of Overwatch.