At some point you’ve probably heard someone say that they “plead ignorance.”

However, in federal criminal defense, the general rule is that ignorance of the law is no excuse. Federal Criminal Defense: Mistake of Fact

One exception is when you were genuinely mistaken about the facts or circumstances leading to your criminal charge.

For example remember the time you borrowed you friend’s car, and the friend forgot to tell you about the three kilos of cocaine in his trunk? Some friend huh.

If you really weren’t aware of the drugs in your friend’s car, then you do have a valid Mistake of Fact Defense to a federal controlled substance possession charge.

Or as a Federal Court said “mistake of fact is a valid defense to a criminal charge when the defendant’s acts would not be criminal if the facts were as he supposed them to be.”

ref:  United States v. Barker, 514 F. 2d 208.

In our example with your friend’s car, you believed that your friend’s car did not have three kilos of Cocaine in the trunk.

Obviously, you were mistaken. But simply driving your friend’s drug free car would not be criminal if the facts were as you supposed them.

This is a super simple and not so realistic example, but it applies to all sorts of federal criminal cases. Including cases that are much more complicated.