Many Acts of Parliament delegate to the executive government the
power to make detailed rules and regulations (legislative
instruments). Instruments made in this way are subject to the
power of either House to veto or disallow them.
In most cases, within 15 sitting days after tabling a senator
may give notice of a motion to disallow the legislative instrument.
If the motion is agreed to, the instrument is disallowed and ceases
to have effect. If a notice of motion to disallow a legislative
instrument has not been resolved or withdrawn within 15 sitting
days after having been given, the instrument is deemed to
have been disallowed and automitically ceases to have effect.