Closure of debate
A motion may be moved in the course of a debate, but not so as to interrupt a senator speaking, that the question be now put. That motion must be put and determined without debate or amendment, and if it is carried the question before the Senate is then put and determined immediately without further debate or amendment. This procedure provides an opportunity for the Senate to decide that debate should conclude and the question before the Senate be determined. It is known colloquially as the "gag".
The closure motion cannot be moved by a senator other than a minister who has spoken in the debate or who has previously moved the closure. In practice a senator is allowed to make a few explanatory remarks before moving the closure.
The motion may be directed only to the question before the chair, so that, if the question is for an amendment to be agreed to, it is only that question which is put without further debate, and debate on the main question may continue.
The closure may be moved in committee of the whole, but may not be repeated within 15 minutes after it has been moved. The closure may not be moved if the Senate is considering a bill under a limitation of debate.
A senator who has moved the closure, if that motion is negatived, may speak later in the debate; this practice is based on an analogy with the rule applying to the adjournment of debate.