Obstruction of and assaults on authorised officers.
286.—If any person—
(a) obstructs or impedes an authorised officer in the lawful execution of his powers and duties as an authorised officer under this Part, or
(b) assaults an authorised officer in the lawful execution of those powers and duties,
that person shall be guilty of an offence under this section and shall be liable on summary conviction thereof to a fine not exceeding twenty pounds or, at the discretion of the court, to imprisonment for any term not exceeding six months.