Chris Carrick

Chris Carrick was a lawyer whose identity House stole in order to gain leverage in his dispute with his landlord in the Season 5 episode Painless.
House's insurance had turned down his claim to fix damaged caused by a water leak because the handyman noted that the damage to the pipes was caused by stress and not corrosion.
In order to gain some leverage, House thought of sending a threatening email to his insurance company. However, he knew that if his name was on it, the insurance company would ignore it. He asked Kutner the name of the lawyer and law firm that represented the hospital when Kutner set a man on fire and Kutner gave him Carrick's name. House signed Carrick's name and firm to the email.
A few days later, Carrick showed up with a bill for his services, then threatened House with a lawsuit if he ever tried the stunt again.