Is Amnesia a Defense to a Criminal Charge?

In most cases, a person has to act either intentionally or recklessly to be considered guilty of committing a crime.

But, there are certain circumstances (such as being forced against one’s will) where you can argue in court that you weren’t at fault.

A defense that lies somewhere in between is amnesia.

If you can’t remember committing a crime, were you truly responsible for it? The answer may surprise you.

Let’s take a look.

What Is Amnesia?

Ther term ‘amnesia’ is typically used to describe a form of temporary memory loss. Other symptoms include the inability to recognize familiar people or places, overwhelming confusion, and no recollection of their amnesia episode.

While it’s common knowledge that head trauma may result in a period of amnesia, there are other causes to consider. Some of these are:

  • Side effects of taking drugs
  • Stroke
  • A hysteria caused by emotional shock
  • Seizures

While general memory loss is often only temporary, someone suffering from amnesia will likely never remember what occurred during their episode. So, the loss of memories during this time is permanent.

For example, David may not remember his father’s name after being struck in the head by a baseball, but he will remember it later. He will never remember the ride to the hospital or several hours afterward.

Can You Diagnose Amnesia?

Yes, you can.

And, it’s important that you do receive a medical diagnosis due to the aforementioned abuse of using amnesia as a legal defense.

A medical professional will examine you in multiple areas, including:

  • Balance and cognitive ability
  • Reflexes
  • The ability to comprehend and retain new information
  • The ability to recall common knowledge (the name of a certain color, name of our galaxy, etc.)

The professional may also choose to conduct an MRI to check for potential brain damage.

Afterward, the doctor will provide a statement regarding the tests and their results, which can serve as evidence for your defense.

So, Is it a Viable Defense in Court?

To use as the singular defense for your entire case? No, it isn’t.

But, let’s discuss why.

The problem with using amnesia as a legal defense is that it argues the defendant couldn’t have consciously committed the crime because they weren’t coherent at the time.

Let’s look at a brief scenario.

One Friday night, Andrew decides to attend a house party with his friends. After a few drinks, he decides to go outside with a group of acquaintances and smoke marijuana.

Unbeknownst to Andrew, the marijuana he smoked was laced with PCP. Shortly afterward, he leaves the party without saying anything to anyone.

Andrew ends up walking a quarter-mile to a nearby gas station. He is still feeling the effects of PCP, marijuana, and alcohol. Andrew walks into the store and knocks over shelves before taking handfuls of merchandise and leaving.

Police find him passed out in a nearby field a short while later and immediately arrest him.

Even though Andrew would most likely implore that his lawyer uses his amnesia as a defense that he’s innocent, a judge most likely won’t see things Andrew’s way.

This is due to one glaring issue:

Being unaware of your actions while committing a crime isn’t always evidence that proves that you didn’t actually intend to commit the crime.

So, there’s a high probability that a judge will more or less say “sorry, but not remembering what you did doesn’t make you not guilty.”

Additionally, amnesia is a weak defense to use due to its potential for abuse. Anyone charged with a crime could say “I don’t remember doing that,” “I have no memory of getting arrested,” etc.

When Is Amnesia a Factor in The Courtroom?

Interestingly, amnesia is still an important piece of evidence to bring up in court, and it can directly affect a couple of situations.

Competency to Stand Trial

While you can’t walk into a courtroom and expect amnesia to be the defense that saves you, it can still play a role in your case. In particular, amnesia can be a factor the judge considers when determining your competency to stand trial.

Amnesia can affect the defendant’s ability to discuss the case with their attorney, and also whether or not the defendant can understand the legal proceedings against them.

Additionally, permanent amnesia can also be an obstacle that stands in the way of the trial, since this can cause someone to forget their name, basic concepts such as reading or math, etc.

If a judge deems that a defendant is incompetent to stand trial, the trial must be delayed until competency is restored.


At the very least, amnesia can have a minor influence on the judge’s sentencing decision.

For example, a person suffering from amnesia may not remember colliding with another vehicle while they were driving. But, this isn’t enough to prove they weren’t at fault.

This can, however, result in a lesser sentence due to the defendant’s (non-alcohol or drug-related) impaired state of mind.

Keep in mind, though, that this is not a hard and fast rule. It’s not impossible for a judge to completely disregard the defendant’s claim of amnesia and hand out a maximum sentence.

Understanding Amnesia Can Seem Difficult

But it doesn’t have to be.

With the above information about amnesia in mind, you’ll be well on your way to knowing the best defense you should seek in the courtroom.

Want to learn more legal information that can help keep you out of trouble? Make sure to check out the rest of our blog!