Pure speculation. My real answer I already gave which is they are just immoral - easy.

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But the reasons why the number is higher are as follows:

Men are forced into being weapons - women are rarely. They are effectively trained to kill.

Most murders, rapists, etc are repeat offenders and yet each occasion is viewed as a seperate strike against men etc (same when women are repeat offenders for things).

Cultures have different education expectations and it has been shown many times that men do better in apprenticeship vs group learning. So men are at a disadvantage to learn proper skills and are in uncomfortable situations which would increase the likelihood of a problem.

Men and women have different biological response to stress.....men go typically into fight mode where as women are more likely to be passive when threatened....however women are more likely to seek revenge and to murder and attack when they are able to (poison is common with women serial killers for this reason)

Rape is unique to each culture as to the prevalence.... suggesting it is education/culturally affected....ie....why south Africa and India have so much rape per capita....

But also there is the fact that you are looking for cases which are easily solved....ie...violent cases usually have lots of evidence these days. Quiet crimes less so.

Men are probably more likely to commit crimes which require muscular advantage.....but....in cases where children are involved....may I point you to Nuns....mostly women...lots of deaths....