Pistol-whipping is the act of using a handgun to strike another person. It can be both lethal and non-lethal force.
In season one, Officer Roland "Prez" Pryzbylewski pistol-whips a teenager with his sidearm. The boy is blinded in one eye. Though he is investigated by Internal Affairs for excessive use of force his commanding officer, Lieutenant Cedric Daniels, though furious at Prez' misconduct and carelessness, supports him, helping him escape serious charges.