Alice is on the bus and suddenly BOB (alice has never seen him before) turns up and grabs Alice's cell phone and claims he is keeping it and it is now his own personal cell phone. Alice then says to BOB give my phone back BOB or else I will go to the cops and report this theft.
If Alice would have pulled out her Desert Eagle and shot Bob in the face when he grabs her phone we won't have to worry about blackmail, calling the police or Bob stealing cell phones again!