5. The enactment or obligation does not prevent or penalise the disclosure of relevant information by contractor A or an employee of his to another Department, Minister, office-holder or district council ( “authority D”) or an authorised officer of that authority if—N.I.
(a)the disclosure is necessary or expedient for the purpose of facilitating the exercise of the relevant function, a related function or a function of authority D;
(b)the disclosure falls within a description of disclosures certified by authority A (whether in the authorisation or otherwise) to be capable of being so necessary or expedient; and
(c)the information could be lawfully disclosed, for that purpose, by authority A to authority D.