21Obstruction
(1)A person who wilfully obstructs any person acting in the execution of this Part of this Act, or of any byelaw or warrant made or issued under it, shall be liable—
(a)if the court is satisfied that he committed the offence with intent to prevent the discovery of some other offence under this Part of this Act, or if he has within the previous 12 months been convicted of an offence under this subsection, to a fine not exceeding £50 or to imprisonment for a term not exceeding one month;
(b)in any other case, to a fine not exceeding £20.
(2)A person who—
(a)fails to give to any person acting in the execution of this Part of this Act, or of any byelaw or warrant made or issued under it, any assistance which that person may reasonably request him to give ;
(b)fails to give to any such person any information which that person is expressly authorised by this Part of this Act to call for or may reasonably require; or
(c)when required to give any such information, knowingly makes any misstatement in respect thereof,
shall be liable to a fine not exceeding £20; but nothing in this subsection shall be construed as requiring a person to answer any question or give any information, if to do so might incriminate him.