It is possible to duplicate your character and all stuff that he carries, by disconnecting from the server in the right moment. He will stand at your spawnpoint.

You can interact with him, e.g. putting him in handcuffs. He is known as "unknown identity". You can kill him with guns.
If you try to kill him with a melee weapon he will bleed and become unconscious, but he will standup after some seconds. He won't die this way

It's easier to hit the correct moment, when you have a high ping to the server.