When haters go public

My local newspaper recently reported a story of a murder-suicide. A man shot his estranged wife at her workplace and then shot himself. This is already the second such incident in a month, but in this case, two of the woman’s coworkers were also shot (they survived). I was very frustrated by this story because it seems to happen everyday, but then I was even more frustrated by the comments that followed the story on the website.
One commenter praised the gunman as a “hero” because he would not take an insult “lying-down”. The insult being that his wife had just filed divorce against him one week before the shooting. The commenter then went on to denounce the family court system, calling it unfair to men, that it enriches all the gold-digging wives. At some point, the commenter mentioned his personal grievances against his ex-wife.
Other commenters on the board were alarmed by his statement. They argued against him, and eventually his post was taken down. Still, I felt very disturbed. This commenter obviously had such deeply-entrenched hatred against women that he would justify murder. In fact, he could be a present danger to his own ex-wife. However, because of internet anonymity, nothing could be done.
And then I thought, what if there was no anonymity? What if we know the commenter’s identity, his workplace, and we have firm evidence that he harbors hatred against his ex-wife and isn’t beyond using lethal force, could any action be taken against him? I am not too optimistic about that either.
Recently I read a survey about domestic violence and the workplace. 85% of the batterers admitted that their employers or coworkers knew about their abusive behavior. Apparently, the employers couldn’t take any action. They are barred by law to dismiss workers for domestic abuse.
So what kind of consequence is there for an abuser to publicly admit that they abuse? Every sense of justice I have screams that there should be. As the workplace shooting demonstrates, domestic violence can easily spew into a public security issue. I feel like there should a strong safety-net to protect potential victims before the tragedy strikes.