Road Traffic Act 1961
Prohibition of unauthorised holding or getting on to vehicles.
99.— (1) A person shall not hold on to, or get on or in to, a moving vehicle in a public place.
(2) A person who contravenes subsection (1) of this section shall be guilty of an offence.
(3) Where a person is charged with an offence under this section, it shall be a good defence to the charge for him to show that there was lawful authority for the act complained of or that otherwise there was reasonable cause therefor.