(1) A person shall not do any act (whether of commission or omission) which causes or is likely to cause traffic through any public place to be obstructed.
(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 it was due to unavoidable accident.