4If on investigating any matter a conciliation committee form the opinion that any such act as aforesaid has been done and either they are unable to secure such a settlement and assurance, or, as the case may be, such an assurance as aforesaid, or it appears to them that the act was done in breach of a relevant assurance, they shall make a report to that effect to the Race Relations Board and the Board shall consider the report and shall either investigate the matter themselves or, without investigating it, determine whether or not to bring proceedings under section 19 or 20 of this Act.