Originally Posted by S.Brett
Maybe the attack on his sister with a knife could have been the only incident that the family, the police and doctors ever having seen. Apart from some outbursts of rage.
The Ripper was not someone who ran around the streets brandishing a knife. We can be pretty sure there would have been reports of this if & when it happened. In fact it is far more likely that his victims never saw a knife.
The Ripper was a strangler, who, from what we can tell, only drew the knife when his victims were out cold.
Did Kozminski ever threaten to strangle anyone?