21. Where, in any proceedings under section 3, 3A, 4 or 9 of this Act or Part 2 of the Housing (Miscellaneous Provisions) Act 2014, a member of An Garda Síochána or an officer or employee of a housing authority states that he or she believes that a person is or has been engaged in anti-social behaviour, then, if the Court is satisfied that there are reasonable grounds for such belief and that another person would be deterred or prevented by violence, threat or fear from providing evidence in that regard, the statement shall be evidence of such anti-social behaviour.]