As with most areas of law, the short answer is ‘it depends‘. Reasons for judgement were released this week by the BC Supreme Court, Victoria Registry, canvassing this area of law.
In today’s case (Hurn v. McLellan) the Plaintiff was injured in a 2007 motor vehicle collision. It was a ‘t-bone‘ crash that occurred in a parking lot. The Plaintiff started a lawsuit and ICBC admitted the issue of fault in the Pleadings on behalf of the other motorist. As the lawsuit neared trial ICBC brought an application seeking permission to withdraw the admission of fault. Master Bouck dismissed ICBC’s request finding it would be prejudicial to the Plaintiff’s interests. In doing so the Court provided the following useful summary of the law:
 …There are similar and overlapping considerations for the court on these two types of applications. However, to adopt the submissions of plaintiff’s counsel, the “high bar” threshold to obtain leave to withdraw an admission must be met before the “low bar” threshold to obtain leave to amend a pleading will follow. Thus, the legal test to be met by the defence is with respect to the withdrawal of an admission.
 Rule 7-7(5) of the SCCR provides that:
7-7(5) A party is not entitled to withdraw
(a) an admission made in response to a notice to admit,
(b) a deemed admission under subrule (2), or
(c) an admission made in a pleading, petition or response to petition
except by consent or with leave of the court.
 The principles which govern an application to withdraw an admission of fact are as follows:
1. Whether there is a triable issue which, in the interests of justice, should be determined on the merits and not disposed of by an admission of fact;
2. In applying that test, all of the circumstances should be taken into account including whether:
(a) the admission has been made inadvertently, hastily or without knowledge;
(b) the fact admitted was not within the knowledge of the party making the admission
(c) the fact admitted is not true.
(d) the fact admitted is one of mixed fact and law
(e) the withdrawal of the admission would not prejudice a party
(f) there has been no delay in applying to withdraw the admission.
Hamilton v. Ahmed (1999), 28 C.P.C. (4th) 139 (B.C.S.C.) at para. 11, as approved in Munster & Sons Developments Ltd. v. Shaw, 2005 BCCA 564.
 More recently, the test has been articulated by the court in 374787 B.C. Ltd. v. Great West Management Corp., 2007 BCSC 582 at para. 27:
As a general rule, the Court must consider whether in the circumstances of the case the interests of justice justify the withdrawal of the admission. The following facts, which are not exhaustive are relevant: delay, loss of a trial date, a party is responsible for an erroneous admission, inadvertence in the making of an admission and estoppel …
 The question of fault for the accident is one of mixed fact and law: Bedwell v. McGill, 2008 BCCA 6 at paras. 33 to 34, foll’g Housen v. Nikolaisen,  S.C.J. No. 31,  2 S.C.R. 235 at para. 27 (S.C.C.), per Iacobucci and Major JJ.
 However, whether the admission sought to be withdrawn is one of fact, law or mixed law and fact, the same legal test applies: Nesbitt v. Miramar Mining Corp., 2000 BCSC 187 at para. 6.
 It is not enough to show that triable issue exists. The applicant must show that, in all of the circumstances, the interests of justice require the withdrawal of the admission: Rafter v. Paterson(November 7, 2007), Vancouver No. B924884.
 Moreover, even if a trial date is not imminent and the applicant gave early notice of the proposed withdrawal of the admission, delay in bringing an application for such relief might in itself be a “concern that cannot be overcome”: Sureus v. Leroux, 2010 BCSC 1344.