Sinn Fein has confirmed Gerry Kelly removed a clamp from the front wheel of his car, after footage emerged on social media.
The footage appears to show the Northern Ireland Assembly member kneeling down to remove the orange device from the vehicle's right-hand wheel, before resting it against a nearby wall.
A pair of bolt cutters appear to be lying beside the wheel.
A party spokesman said: "Yesterday, Friday 2 February, Gerry Kelly MLA returned to his car after an early morning gym session to find that his car had been made immobile by a clamp just after 7.20am.
"He removed the clamp from the front wheel. He left the device nearby and drove off to pre-arranged meetings.
"His solicitor is dealing with the matter and he will be making no further comment at this time."
Traditional Unionist Voice (TUV) leader Jim Allister said: "This must swiftly become a matter for police investigation and action. It must be demonstrated he is not above the law.
"His audacious taking of the law into his own hands must not go unchallenged by the law enforcement agencies.
"Kelly should resign after this self-serving, law-defying episode. It is time for another Sinn Fein representative to exit the public stage courtesy of his own brazen defiance of law and order."
Mr Kelly is a senior party figure and has formerly held the position of junior minister at Stormont.
During the Troubles the veteran republican was convicted for his part in the IRA bombing of the Old Bailey in 1973.
Ten years later he took part in a mass escape from the Maze paramilitary prison.