Constitutionality of legislation – Whether section 20 of the Independent Commission of Investigations (INDECOM) Act is unconstitutional – Effect of section 20 conferring on the Commissioner and investigative staff of INDECOM, in the exercise of their duty, like powers, authorities and privileges as are given by law to a constable – Whether INDECOM’s officers have the powers of arrest and charge – Whether INDECOM’s officers having such powers would undermine the Office of the Director of Public Prosecutions