A withdrawal effectively leaves the claim undefended since it has the effect of canceling any statement of defence.
The wording of court rules differs from jurisdiction to jurisdiction but all provide some sort of mechanism for a defendant to withdraw his or her statement of defence or counterclaim.
Because it is similar to the plaintiff's prerogative to discontinue, a typical rule of court would group both processes within the same rule. For example, in the Canadian jurisdiction of Manitoba, Rule 23 of the Court of Queen's Bench Rules, 2009, is entitled Discontinuance and Withdrawal, and includes this:
"A defendant may withdraw all or part of the statement of defence with respect to any plaintiff at any time by filing, and serving on all parties, a notice of withdrawal of defence ... but where the defendant has cross-claimed or made a third party claim, leave to withdraw must be obtained from the court....
"Where a defendant withdraws the whole of the statement of defence, the defendant shall be deemed to be noted in default."
These rules are similar to Rule 23 of the Ontario Rules of Civil Procedure (2009), and Rule 36 of the British Columbia Supreme Court Rules (2009).
A withdrawal is rarely done as an abject surrender by the defendant to the plaintiff and his/her claim and the court (if a defendant did not wish to defend, he or she likely would not have filed a statement of defence in the first place). Rather, it is usually filed as part of an out-of-court settlement of the litigation.
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