Mistake of Law，翻译为“法律错误”，英文释义为：Mistake about the legal effect of a factual situation.。是指行为人在实施故意犯罪过程中，对自己的行为在法律上是否构成犯罪或者在法律上应受到什么样的处罚所发生的错误认识。刑法错误的一种。法律错误有以下三种情况：

（1）假想不犯罪。行为人的行为在法律上已经构成故意犯罪，而行为人误认为自己的行为不是犯罪。理论上一般认为，这种法律错误不阻却故意责任的成立，尽管行为人误认为自己的行为不构成犯罪，但也应当负故意犯罪的刑事责任。（2）罪名错误。行为人对自己的犯罪行为在法律上成立的罪名存在着错误认识。罪名错误不影响行为的犯罪性，应根据刑法的规定依法定罪量刑。

（3）处罚错误。行为人对刑法如何处罚自己的行为产生的误解。包括两种情况：一是行为人的犯罪行为应受到较重的处罚，而行为人误认为不受处罚或者会受到较轻的处罚。二是行为人的犯罪行为应受到较轻的处罚，而行为人误认为会受到较重的处罚。处罚错误不影响犯罪行为的社会危害性及其刑事责任，司法机关应依照刑法的有关规定依法量刑和心理的总和。

Mistake of fact，翻译为“事实错误”，英文释义为：Any mistaken belief other than a mistake of law. Examples include erroneous beliefs about the meaning of some term or about the identity of some person.“法律错误”的对称。是指行为人在实施故意犯罪过程中，对可能影响其刑事责任的客观事实所发生的错误认识。刑法错误的一种。在刑法理论上，根据事实错误与罪条的关系，事实错误可以划分为具体的事实错误与抽象的事实错误。根据事实错误的具体形态，刑法错误在理论上又可以划分为对象错误、手段错误、行为性质错误、因果关系错误等。

参考双语例句：

The Lands Tribunal may extend the period within which notice of a claim must be delivered to the Director of Lands if it considers that the delay in delivering notice of the claim was occasioned by mistake of fact or mistake of any matter of law (other than the relevant provision in section 12(2) or by any other reasonable cause or that the Crown is not materially prejudiced in the conduct of its case or otherwise by the delay.

土地审裁处可延长向地政总署署长送递索偿通知书的期限，若它认为送递索偿通知书的延误是由某项事实错误或法律错误(但不包括第12(2)条的有关条文)或任何其他合理因由所致，或延误不会严重不利于官方或其案件的进行。

As it has stated several times, it will review such a discretionary decision only if it was taken in breach of a rule of procedure, or if there was a mistake of fact or of law, or if some essential fact was overlooked, or if there was abuse of authority, or if some clearly mistaken conclusion was drawn from the evidence.37 5.1.1.2 Restructuring and abolition of posts: extent of the Organization’s power in respect of its staff members.

正如它多次强调的那样，它不会审查这样一个属于斟酌权的决定，除非它违反了程序规定，同事实有出入或在法律上有错误，忽视了某些重要事实，存在滥用权力的行为或者显然得出了错误的结论而被从案中撤销的情况下38。

It was suggested, however, that the notion of “mistaken grounds”, which was not really legal terminology, be clarified by stating that the grounds in question were either attributable to an error of fact or of law, or were baseless.

但有人指出，“不当理由”这一说法并非真正的法律术语，应明确声明相关理由到底归咎于事实或法律错误还是毫无根据。