On February 11, 2015, a Texas woman driving a minivan was waiting at a red light when she was struck from behind by another vehicle. Angry that this collision might have injured her teenage son, who was a passenger in the minivan, the woman approached the driver of the other vehicle and, with the help of her boyfriend, wrestled him to the ground. At that point, police arrived and arrested the other driver.

As it turns out, he was allegedly fleeing – in a stolen car – from a robbery, and the collision happened because he was actively being chased by police. It’s not clear whether the woman who accosted him knew this. From published reports, it may be that she was simply (as police described her) a “mama bear” vigorously protecting her cub.

Let’s assume that she didn’t know that she was helping to apprehend a fleeing suspect. Could she be charged with assault and battery? It’s an interesting question that touches on two sometimes tricky areas of criminal law: the potential defenses of “mistake” and “impossibility.”

Most if not all jurisdictions consider a mistake of fact to be a valid legal defense. For example, if Jim sells a bag of what he believes to be sugar to an undercover agent, and it turns out that the substance is cocaine, Jim should not be found guilty of selling illegal drugs.

On the other hand, a mistake of law is generally not considered to be a valid defense. Thus, Jim could not defend himself from a charge of illegal gambling by showing that he truly believed that betting was legal in his jurisdiction. We say that “ignorance of the law is no excuse,” and indeed allowing mistake of law to be a valid defense would only encourage ignorance of the law.

In a similar way, when we analyze attempted crimes that were never completed, most jurisdictions apply the rule that “factual impossibility” is not a defense. For example, if John pays money to an undercover officer posing as a prostitute, he is guilty of attempting to engage in prostitution (and perhaps other crimes as well) even though, as a factual matter, it was impossible for him to actually complete the offense.

In contrast, “legal impossibility” may be a defense. An example used by one of our law school professors involved a gang that believed it was illegal to withdraw money from one’s own bank account on Sundays. No matter how elaborately they plot and plan to withdraw money from their own bank accounts on Sunday, they should not be found guilty of a criminal conspiracy or attempt because it was impossible for their plan to violate the criminal law.

How, then, does all of this apply to “mama bear”? Let’s assume (and it’s a fair but not certain assumption) that a citizen who knew that the offending driver was fleeing from a robbery in a stolen car had the right to use reasonable force to effect a citizen’s arrest. Let’s also assume that the amount of force used by “mama bear” was reasonable.

This means that the act that the woman committed was a legal one, even though she committed it for a different reason – a reason that would have made her assault illegal.

The question is whether her intent can turn a legal act into an illegal one. While the answer is far from clear, we believe the better answer is that her actions remain legal even though she didn’t know at the time that they were. This case seems to fall closest to the rule about “legal impossibility.” Professor Rollin Perkins, in his book, Criminal Law, wrote that “Attempting to do what is not a crime is not attempting to commit a crime.” And indeed, there are court decisions from around the country holding, for example, that attempting to bribe someone you mistakenly think is a juror, or receiving what you mistakenly believe to be stolen goods, are not crimes.

If we accepted that “mama bear” was guilty of a criminal assault under these circumstances, it would seem very anomalous that the family in the car next to her – if they happened to know about the police chase – could legally have done exactly what “mama bear” could not.

The solution to Mama Bear’s legal puzzle may be less complex than it appears at first blush. The crash occurred in Texas. Article 14.01 of the Texas Code of Criminal Procedure authorizes citizens to arrest individuals for committing offenses against the public peace. Texas courts interpreted, “breach of the peace” to mean any actual or threatened violence, including erratic driving on populated streets where no accident occurred. See, Kunkel v. State, 46 S.W.3d 328 (Tex. App.-Houston 2001). Under this rule, Mama Bear’s actions appear likely to be protected by the law, as violence actually occurred on Texas streets when the get-away car slammed into her van at the light.

Finally, we would like to point out that this incident is not exactly an example of best behavior on the road. It is easy to imagine that assaulting another driver after a traffic accident could end much differently than this particular story did.

Co-Contributor Matthew Brungo, Esquire