'Ignorance Of The Law' Question

We all know that ‘Ignorance of the law is no excuse,’ but I’m wondering if there are indeed any cases where it could or would be a valid defense?


In criminal law it may be a mitigating factor in determining sentence, though ingnorance of a statute, as the saying goes, is not a valid defense.

In civil law, ignorance may be somewhat of a defense in cases because foreseeability is almost always a required element. Suppose I bought a house with a fruit-bearing plant in my yard which, unbeknownst to me is poisonous. When the fruit ripen, they may pose an “allurement” to the neighbourhood kids who come onto my property and pig out. If I can demonstrate that I was ignorant of the fact that the trees were poisonous, I my not be liable, whereas if I was aware of the fruit’s toxicity, I may be held liable.

Hrdygrdymn, assuming you’re a lawyer, is that an actual case you are describing (about the poisonous fruit)? There is a rather similar case in Dutch law that I’m researching and it would be interesting to see an analogous case in US law.

But that’s not an example of ignorance of the law; it’s ignorance of a fact, namely the hazardous nature of the tree. If you know the tree is hazardous, you can’t say, “But I thought since it’s on my property, I couldn’t be liable to someone who came on to my property without my permission.” That would be ignorance of the law.

This is digging way back in my memory, so forgive me for not remembering the case name, but there was a case in the US Supreme Court where a man collected some spent shells that were near a military firing range. He was arrested for stealing federal property. The Court reversed his conviction based on the idea that ignorance of the law can be an excuse where the law in question is a technical one that the person could not or would not be expected to know about. Those weren’t the court’s exact words, obviously, but that was the gist of the ruling. I will see if I can find the case, but maybe someone will remember it and clarify the exact ruling.

Fair enough, N Piper. The example I cited is not ignorance of the actual legislation because ignorance is, as the saying goes, never an excuse. I am merely claiming that ignorance may be a factor in challenging the plaintiff’s required element of foreseeability. While this is not the same thing as using ignorance of the law as a defence, it is using ignorance as a defense which is why I said it was “somewhat of a defense”.

TTT I am not a lawyer, merely (or thankfully) a law teacher. The example I gave is, I believe, based on a British Common Law case, but I couldn’t give the cite.

Hrdygrdymn: the “poison tree” thing is not an example of ignorance of the law, it’s an “attractive nuisance” issue and a pure question of negligence. See the old case Sioux City & Pacific Railroad Co. v. Stout, 84 U.S. 657 (1873).

Oh as for the OP, the short answer is that it depends on the statute and Congress’ intent. For example, many of our complex tax laws do require knowledge of the law for one to be found guilty of a violation. See Bryan v. United States, 524 U.S. 184, 193, 118 S.Ct. 1939, 141 L.Ed.2d 197 (1998).

So the general rule is that “ignorance of the law is no excuse” coupled with “all citizens are presumed to know the law” … but there are exceptions, typically reserved for complex laws that the average person acting in good faith wouldn’t know they are violating. IANAL by the way.

This strikes me as unjust. Why would I be liable in such a case? The kid is not only trespassing, but actually engaging in a deliberate act of theft against my belongings (the fruit on my tree). It is not as if I had planted land mines on my yard (which would, indeed, pose a reasonable threat to anyone who might accidentally step into my property.

qusar: well aside from the fact that mines are contraband to the general public…

The fruit bearing tree problem: the person who bought the tree and planted it in their front yard can be found criminally neglegent, along with penalties for not clearing the plantation of the tree with the neighborhood/city/county zoning committy (whichever is applicable)

if the lady did know the tree was poisionous that falls under criminal neglegence, if she knew and offered children to eat the fruit thats direct intent and then becomes a more serious crime. If she did NOT know the fruit was poisionous then she may be criminally neglegent, along with the person who SOLD her the tree (if they did not give enough warning of the nature of the tree)
To the OP a better example of “ignorance of the law” might be not seeing a stop sign, or being unaware of the speedlimit in a given area.

There are no ‘straight’ exceptions to that rule. HOWEVER there are certain people who cannot be prosecuted (SP?) such as Idiots (persons mentally handycapped, by legal defination are known as Idiots) Foriegn diplomats with immunity. There are others too but I don’t particularily feel like looking for my book right now.

Also there are other loopholes for certain crimes. Such as murder cannot be commited by an animal. However if the animal has an owner he or she can be held criminally neglegent if they did not know the animal had escaped, or can be found guilty of murder if the owner of the animal purpously used the animal to kill the victim. However proving intent of using the animal as a deadly weapon against the victim is VERY hard to do in most cases.

-x out

Quasar, children are presumed incapable of controlling their actions, and incompetent to manage their affairs., though they become increasingly responsible for their actions as they grow up. You are liable for any harm that comes to a child due to your failure to take their irresponsibility into account.

Fair enough. But let’s for the sake of argument assume that the person who stole my oranges was an adult, and thus fully aware of the implications of his act. Woud I then be liable for any harm occuring to him?

Ignorance of the law is no excuse is a maxim many of us have heard—or ignorantia legis neminem excusat for Blackstone-minded Dopers. The rationale for the rule is a bit unclear.

It can’t be to encourage knowledge about the law because the doctrine provides a disincentive to research the law since one can’t rely on it; indeed, the purpose of the doctrine must be to keep people in ignorance of the law and to encourage them to act “morally.”

Alternatively, it could be that the doctrine is motivated to avoid subjectivity in the law. It’s because laws are unavoidably vague such that persons can disagree infinitely regarding their meaning. At some point, debate regarding the meaning of a law must end: the courts must determine its meaning. If a mistake of law coulde excuse, the result would be that the law would, for all practical purposes, lose its objective meaning—it would mean whatever a person subjectively (and perhaps incorrectly) thought it meant. Yet a legal order implies the rejection of such contradiction; a legal system favors objectivity over subjectivity and judicial process to individual opinion. But this doesn’t necessarily hold, because a mistake of law defense doesn’t mean that the law means whatever the defendant thinks it does. The meaning of the law would remain stable, but the defendant would simply be excused for a violation assuming that an ordinary law-abiding person would have also misunderstood the law in question. To punish one whose mistake of law is reasonable seems contrary to the retributive notion that punishment should be conditioned on a showing of moral blameworthiness.

A final jsutificaiton for the doctrine might be to deter fraud. People would contrive claims of mistakes solely to get an exculpatory notion before the jury if a mistake-of-law defense were recognized generally. Courts would become hopeless enmeshed in insoluble questions regarding the extent of a defendant’s knowledge of the relevant law. Or would they? Is this question so much harder to investigate than the defendant’s sanity or whether the defendant had the intent to kill, or whatever?

But rationale for the rule aside, the OP calls for exceptions to the rule. Kalt is dead on in saying that when knowledge of the law is an element of the offense, an honest mistake of law, even if unreasonable, exculpates. There’s some confusion about statutes that don’t explicitly say one way or the other whether knowledge of the offense is an element of the offense. Courts seem to construe statutes to require knowledge of the law when necessary to prevent innocent behavior from being criminalized where the statute applies to citizens at large (as opposed to a normally-highly-regulated group), or when the law is very complex. Some example cases:

  1. U.S. v. International Minerals & Chemicals Corp.—statute made it a crime to “knowingly violate” a regulation of the Interstate Commerce Commission regarding transportation of corrosive liquids. Court held that state only had to prove that the defendant knowingly committed actions that violated the regulations; i.e., mistake of law defense denied.
  2. Liparota v. U.S.—statute made it a crime to “knowingly use” food stamps in an unauthorized manner, e.g., at a store that charges above-normal prices. Court held that State had to prove that the defendant knowingly committed actions knowing that they violated regulations; i.e., mistake of law defense recognized…
  3. Ratzlaf v. U.S.—statute made it a crime to “knowingly” structure a transaction to evade a financial institution’s reporting requirement. The defendant tried to pay gambling debt to casino in cash, but casino had him buy a bunch of cashier’s checks to evade reporting. Court held that State had to prove that the defendant knowingly committed actions knowing that they violated regulations; otherwise innocent behaviors such as structuring to avoid an audit, to decrease likelihood of burglary, or to keep a former spouse unaware of defendant’s wealth. I.e., mistake of law defense recognized.
  4. Bryan v. U.S.—statute made it a crime to “willfully” deal in firearms w/out a license. Court held that State had to show that the defendant acted with knowledge that his conduct was illegal, but not that he knew of the existence of the statute with which he was charged. Defendant, who had shady business tactics (used straw purchasers and assured them he’d shave off serial numbers), knew his conduct was illegal. I.e., a quasi-mistake of law defense recognized.
  5. U.S. v. Cheek—Defendant, an airline pilot, on the basis of advice, honestly believed that wages didn’t constitute “income” for purposes of federal income tax, and that he didn’t have to pay income tax b/c it was unconstitutional; judge instructed jury that his mistake of law had to be reasonable to exculpate charge of “willfully” failing to file tax return. Held: even an objectively unreasonable misunderstanding of the law, if honest, can negate the specific intent requirement of “willfulness” in federal criminal tax offenses; however, a belief that laws are unconstitutional isn’t ignorance. I.e., mistake of law defense recognized, but only certain types of mistakes credited.

But this is the only situation in which a mistake of law will exculpate a criminal defendant. Non-Criminal Law Mistakes; i.e., an honest mistake about other law (usual non-penal), will exculpate even if unreasonable, in contrast to a same law mistake, which is not a defense. Example: Regina v. Smith: Defendant damages wall panels he installed in apartment he was leaving to retrieve stereo wires he put in with the landlord’s permission. Then charged with the crime of destruction of property belonging to another. Defendant claimed mistake of law because believed property was his. Held: No crime because defendant’s mistake of law negates mens rea requirement that he intend to destroy property “belonging to another.”

Then there are the “true” mistake of law defenses. The above mistake of law defenses aren’t really affirmative defenses, but rather negate one of the elements of the crime. These are affirmative defenses to crimes where you don’t have to know about the crime in order to be convicted.

Reasonable Reliance on Statement of Law: a defendant has a defense to a charge if he can show that he acted “in reasonable reliance” on “an official statement of the law, afterwards determined to be invalid or erroneous, contained in (1) a statute or other enactment; (2) a judicial decision, opinion, or judgment; (3) an administrative order or grant of permission; or (4) an official interpretation of the public officer or body charged by the law with responsibility for the interpretation, administration, or enforcement of the law defining the offense.” Model Penal Code §2.04(3)(b)

Note that the statement must actually permit the conduct in question, but then later be determined to be erroneous. Here’s an example case. In People v. Marrero, the defendant, a federal corrections office, brought a gun into a nightclub believing he was allowed to because a statute prohibiting unlicensed possession exempted corrections officers of any penal corrections institution. In actuality, the statute only applied to state correctional officers and never applied to federal correctional officers. The court held that the defendant’s personal misunderstanding of the statute, even though honest and reasonable, didn’t excuse his criminal conduct. Mistake of law only excuses if statute once allows conduct and later found erroneous.
Official interpretation: a sort of entrapment by estoppel notion. In some jurisdictions, this will constitute a defense – but not all. Note that even in jurisdictions that recognize this defense, it takes a lot before an interpretation is “official.” Your lawyer’s telling you about the law won’t count. What a police officer tells you won’t cut it either. Perhaps a considered opinion by the district attorney might work—but there’s no guarantee. In jurisdictions that don’t statutorily recognize this defense, a limited form of it will nevertheless be enforced by the courts applying the due process clause of the constitution. For example, in Raley v. Ohio, the defendants invoked their 5th amendment privilege before a state government commission investigating “un-American” activities after the commission told them that they could. This advice was erroneous, as the 5th amendment didn’t apply to this sort of proceeding, and so the defendants were convicted of contempt. On appeal to the US Supreme Court, their convictions were reversed as a denial of due process, in that the defendants reasonably relied to their detriment on the official position of the commission that refusing to testify would not constitute a crime.
Secret Law. Obviously, there are serious concerns when the statute defining the offense not only isn’t known to the defendant but also hasn’t been published or otherwise reasonably made available prior to the conduct alleged. In Lambert v. California, an ex-felon was convicted of an ordinance of which she was unaware that required felons to register their presence with the city. The Court struck down the statute as violating the due process clause, but emphasized first that the statute was a “malum prohibitum” – basically a regulatory offense, as opposed to a “real” crime like murder or rape. Second, the court talked a lot about how the statute imposed a duty to act based on a status condition. So this “secret law” defense may be somewhat more limited than may first appear.

How does that work where certain laws or regulations have to be posted like speed limits, no parking signs, or private property signs on not-so-obvious private land in order to nab someone?

If some punk kid loosened the fastener and took down the only 20mph speed limit sign to hang on his wall from a zone normally 30mph, would you still be held accountable (since you didn’t know that the speed limit had changed)? Same for a stop sign?

Are there not some regulations about posting no parking signs in places where people could be expected to see them (like no 6" square signs written in latin 30 feet up a wall)? Is ignorance a defence there?

Uhhhm, the post before mine wasn’t there when I previewed… and I must admit my legal litteracy isn’t quite good enough to know whether my question was just addressed… :confused: Might have been with that last paragraph.

mmmiiikkkeee: the speeding/parking thing is likely to be not a “true” mistake of law defense (in that if the sign isn’t posted, it’s a secret law), but rather the mistake of law negates an element of the offense. In other words, having the speed limit posted or whatever is required by the ordinance criminalizing speeding. So if someone steals the sign indicating that the speed limit on a certain stretch of road is only 20 mph, then you’d get off.

I disagree. I think it is extremely clear and simple to understand. It is virtually impossible (in most cases) for a prosecutor to prove ignorance OR knowledge of the law. To require this of the prosecution would make the job enormously more complex.

Look at the examples in this very thread about the fruit tree. There are nearly as many opinions about the legal status of the tree owner as there are posters. Should a prosecutor need to sort our posters by their legal knowledge, and prosecute (or decline to) accordingly?

It may just be a matter of emphasis, but the “attractive nuisance” theory is not really “a pure question of negligence.” There is an absolute liability component as regards children. If you have a swimming pool in your backyard and have it completely secured with a fence, alarm system, etc., you may still be liable under the “attractive nuisance” theory. This applies only to children.

**Mr. Hand’s ** post is excellent. (Any relation to Learned?) I might add, as already been alluded to, that ignorance of the law does not apply to esoteric laws that an ordinary person would be ignorant of, such as those existing in tax laws and regulartions and Social Security laws and regulations. In fact, some of the regulations in 20 CFR 404 and 416 (Social Security) specifically state that ignorance of that regulation would exonerate one from the provisions thereof.

Interesting example re flora which once again IMO demonstrates the stupidity of American law. I guess no-one in America has rhubarb (poisonous leaves); yew, rosehips, deadly nightshade, (poisonous berries); daffodils (poisonous stalks) or any number of other common garden flora which are in some way poisonous? Children will try and taste anything.

One reference: http://aggie-horticulture.tamu.edu/plantanswers/publications/poison/poison.html

Surely it is the parent of the child - or the adult supervising the child - who is responsible?

Those plants are not poisonous if taken in small quantities, such as a child may ingest. But, more importantly, those are not “attractive” to children, leastwise as to eat; whereas, pools, playlots, open ditches, etc. are. The attractive nuisance theory applies only to things that are attractive to the average child.

Sure, parents have to take some responsibility, but a parent cannot watch over the child all the time when the child is out playing, unless he or she is a tot. The theory is that if you are going to put those things on your property, you must expect that a child will be attracted to them. It therefore behooves you to prevent the child from entering the pool, ditch, etc. Reasonable measures to prevent this are not sufficient. You must make it impossible.