How could a criminal forget a crime? [closed]

Off the top of my head, solmnambulation and memory-impairing drugs are probably the easiest and most probable. Human memory is somewhat frail. In real life this generally impacts the accuracy and availability of memories, but yes, under the right circumstances people can fail to remember having done something. Many things affect memory, and with a little research I'm certain you could find at least ten scenarios that I'm not even thinking of right now.

I am working off of the assumption that you're not interested in trauma-related memory suppression.

1) Sleep-walking is not uncommon, and people who sleep-walk are able to perform all sorts of complex actions while immersed in slow-wave sleep. Look up homicidal sleepwalking on Wikipedia, it's a hoot. As a bonus some medications can cause sleep-walking as a side-effect, including a certain popular insomnia aid.

2) Certain drugs can cause memory loss or poor memory formation. One such is GHB which has gained some notoriety for its use in date rape. It's also occassionally found to have been used in cases of mugging and the like, and it can be difficult to detect. There are certainly other drugs that affect memory, too.

3) Just in case, there is always the possibility of post-traumatic memory loss. In fiction (especially movies) one commonly finds this trope in conjunction with hypnosis. Memory repression hearkens back to Freudian psychoanalysis. This choice has a strong whiff of pop-psychology, and hypnosis therapy in particular is highly controversial.

Hopefully these options can give you something to chew on.

posted over 9 years ago

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lea‭

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I might suggest the idea of fugue states. While more commonly caused by drug or alcohol abuse, they can also be caused by epileptic seizures.

My father experienced Grand mal seizures and if he had a seizure while no one else was around, was sometimes found later with no memory of the seizure or the time before or after it. Later in life, when he was on a number of heavy medications to address them, he specifically began doing (or attempting to) dangerous things directly after a seizure (like standing in front of an oncoming train believing that he was impervious). He had no conscious memories of any of his activities or even his seizure.

posted over 9 years ago

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phantom42‭

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Protein synthesis is required for memory consolidation, so you can use protein synthesis inhibitor to block formation of long term memories in theory. See Gold. Protein synthesis inhibition and memory: formation vs amnesia (2008) for example.

posted over 9 years ago

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Memming‭

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Some bacterial/viral diseases have been known to affect the formation of new memories (see the famous case study of Clive Wearing).

Perhaps a character is yet unaware of their diagnosis, and things in their life start "slipping through the cracks".

Lack of attention promptly after an event can also interfere with the formation of memory. Perhaps something startling happens to the character exactly after or even during the fatal event. This is a little far-fetched unless the killing itself is somewhat accidental or even incidental, as such a powerful emotion (associated with committing a major crime) would dominate one's attention. But for example, someone could "bump" something on the road, be concerned about it, but before checking up on the matter receive a phone call from one's mum. Two weeks later the character hears about a hit and run and finally realizes it was that fateful bump. Quite a moral dilemma here whether or not to turn oneself in. Perhaps the character calls back her mum to see if she remembers anything notable from the time of that call--looking for clues/salvation/deniability. What a taught conversation that would be. hth.

posted over 9 years ago

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GoldenPandas‭

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I believe this is part of the plot of the movie (spoiler below)

Memento

although I'm going on the Wikipedia summary, as I've never seen it.

I've read at least one sci-fi short story (dystopian future) where criminals went to a black market memory wiper and had their memories erased. The criminal became a different person; that "person" isn't the one who committed the crime.

So I suppose the post-wiped person could become a detective who specializes in cold cases, and she eventually comes across a murder which is starting to sound naggingly familiar but she can't put her finger on why...

posted over 9 years ago

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Lauren Ipsum‭

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