The fMRI might fail to distinguish between memory and a rehearsed story recall. It also might fail to distinguish between lying and thinking before speaking. It is a great improvement, though. we can also order people not to think.
When the state penalizes someone, it is in lieu of them taking the law into their own hands. We don’t want a war in the streets. But when the law does not penalize someone, and that person is not legally allowed to harm them, people just might want to take the law into their own hands.
If you kill someone in self defense or murder, and call the police to report it, that saves you from automatic conviction by them simply proving you did it. Now instead, the question is whether it was self defense. I argue that if we can’t tell which, then the penalty should be 1 year in prison. Prove yourself innocent, and get off free. They prove you guilty, it is life. They should freeze debts and allow 1 month to put your stuff in storage, get temporary foster care for kids, etc, before surrender.
If you believe your life is threatened, you will take the 1 year over the chance of death. If you might face a murder conviction, you might not fire in time even if you are 75% sure this person wants you dead.
If someone does not like you on their turf because they don’t like your face, I suspect a guaranteed year in prison would discourage them from killing you. If they kill and don’t report it, then they get life. The police only have to prove 1 fact: who done it, or was it self defense, not both.
If a man rapes a woman, and we find it true that sex happened, he is fined $500, if he makes just below average income. If we just know they were in the same private room a while, but no sperm, then $250. If that penalty does change her anger enough, she can go kill him and say it was self defense. We would investigate but likely not find enough proof, depending on how well she planned it. In that case, she gets a year in prison. Most likely a woman won’t want to go to jail just because she is upset a guy did not want to pay for a date. If rape did happen, she will try to kill him.
In the old days, they had duels. I think this is a similar way to do just that for the 50-50 cases the state can’t solve.