Can you be convicted of a crime if you didn’t know you were breaking the law? Generally, the answer is yes.
This principle is based on the ancient legal maxim: ignorantia juris non excusat, which means "ignorance of the law excuses not." In other words, individuals are presumed to know the law and cannot use ignorance as a defense in criminal proceedings.
However, there are limited exceptions to the rule:
When can ignorance of the law be a valid defense?
Generally, you cannot claim that you were unaware of the law to avoid prosecution. This applies to all offenses, from minor infractions to severe felonies. Laws apply to everyone, whether or not the laws are known or understood. Without this rule, anyone could evade responsibility for their actions simply by claiming they didn’t know that what they were doing was illegal.
That said, there are a few limited exceptions where ignorance of the law might actually be considered a defense:
Specific intent crimes
While not technically an “ignorance of the law” argument, many crimes require proof of specific intent — meaning that the prosecution must establish that the defendant not only committed an illegal act but also did so with a certain intent or mental state.
Therefore, even if a crime does not require that the person know that what they’re doing is illegal at the time of the offense, the law does require that the actions taken by the person were intended to bring about a particular result. So a person charged with assault may have intentionally used non-consensual force against another by shoving them. But unless the prosecution can prove that the shove was intended to cause injury to the person, they cannot prove the charge.
Other Minnesota examples of specific intent crimes include:
- Burglary (Minn. Stat. § 609.582)
- Theft (Minn. Stat. § 609.52)
- Embezzlement (Minn. Stat. § 609.54)
- Robbery (Minn. Stat. § 609.24)
- Forgery (Minn. Stat. § 609.625)
- Conspiracy (Minn. Stat. § 609.175)
- Fraud (Various statutes, such as Minn. Stat. § 609.527 for identity theft)
For instance, to convict a person of forgery, the prosecution must prove the defendant intended to deceive someone. But if a person unknowingly signed a document under the mistaken belief that they had the authority to do so, they might successfully argue that their lack of intent negated the required specific intent for forgery.
By contrast, general intent crimes only require that the prosecution prove the defendant intended to perform the act itself, regardless of whether they knew it was illegal. For general intent crimes, ignorance of the law cannot be a defense, as the focus is on whether the defendant knowingly committed the unlawful act.
Differences in state or local traffic laws
Traffic laws, for example, can vary between states and municipalities, leading to potential confusion. In cases where local regulations differ significantly from state laws, ignorance might be considered a defense.
For example, a driver accustomed to state traffic regulations might unknowingly violate a local ordinance, such as a unique parking restriction or right-of-way rule. If inadequate signage or notification contributed to the violation, a court may consider ignorance as a defense.
Newly enacted laws
If a law is newly enacted and it is not widely publicized, ignorance might be a valid defense, particularly if the law criminalizes behavior that was previously legal and is not yet widely known.
For example, say a new regulation changes fishing license requirements, restricting certain methods previously allowed. A person who continues using the old method (unaware of the change despite regularly reviewing regulations) might successfully argue that they were genuinely ignorant of the new rule despite reasonable efforts to stay informed.
Other legal exceptions
Some legal precedents and judicial rulings have recognized exceptions to the general rule of ignorantia juris non excusat:
- Tax Law: In Cheek v. United States, the U.S. Supreme Court ruled that a misunderstanding of tax law, if made in good faith, could be a valid defense due to the law's complexity.
- Due Process Considerations: If a law is so vague or obscure that a reasonable person could not understand what conduct is prohibited, a defendant might argue that enforcement violates their due process rights.
- Lambert v. California (1957): The Supreme Court ruled that if a person had no reasonable way to know about a law (such as a local registration requirement for convicted individuals), ignorance could be a valid defense.
- Heien v. North Carolina (2014): The Supreme Court held that even if a police officer mistakenly interprets a law, their reasonable belief can still justify a traffic stop, though it does not excuse a defendant’s legal violation.
- State of Minnesota v. Mikulak (2017): The Minnesota Supreme Court overturned a conviction because the defendant, who was supposed to register as a predatory offender, claimed he didn't know the specific requirements and time frame for registration, and the crime required a knowing violation. Conversely, if a crime is a "strict liability" offense (where knowledge is not an element), then ignorance of the law is generally not a valid defense.
Ignorance of the law vs. mistake of fact
While ignorance of the law is generally not a defense, mistake of fact may be. A mistake of fact occurs when a person has a false but sincerely held belief about a factual situation that, if true, would mean no crime was committed.
Example: A person takes another’s bag from a coffee shop, genuinely believing it to be their own. This would not constitute theft, as there was no intent to steal.
What to do if you’ve been charged with breaking a law you didn’t know about
While "ignorance of the law does not excuse" is the default legal rule, Minnesota and other jurisdictions allow certain exceptions in very limited circumstances. If you are facing criminal charges and believe ignorance of the law may apply to your situation, it is crucial to consult an attorney.
An experienced lawyer can assess your case, determine whether an ignorance-based defense is viable, and guide you through the legal process. Even if ignorance may not be a viable defense in your case, there are other defense strategies your attorney can help you to explore.
Rather than relying on ignorance as a defense, legal representation can help identify the best strategy to protect your rights and get your life back on track.
The first step is a free consultation — call us to schedule one below.
