John Farnham, page-61

Gleason's not entirely correct.

No matter how much subsequent Parliamentary legislation is passed, all of that legislation must be subservient to the wording of the Constitutional Amendment.

For example, whilst legislation can limit the powers of the Voice (because it says so in clause 3 of the Constitutional Amendment - 'matters relating to the Voice'), there's NOTHING subsequent legislation can can do to limit the scope of 'matters affecting ATSI peoples' (because clause 3 of the Constitutional Amendment refers only to "the Voice", not to "the ATSI peoples).