Who could have known that Kevin Janson Neal would turn violent and go on a shooting rampage? One clue might have been the fact that he’d been in jail in January after allegedly stabbing a neighbor with whom he’d been feuding. His mother claims that the neighbor had gotten “slightly cut” in the altercation, but she had to put up $160,000 to bail him out. Neal thought his neighbors were cooking meth and had been feuding with them for a long time:

Neal’s mother told The Associated Press he was in a long-running dispute with neighbors he believed were cooking methamphetamine.

The mother, who spoke on condition she be named only as Anne, lives in Raleigh, North Carolina, where she raised Neal. She said she posted his $160,000 bail and spent $10,000 on a lawyer after he was arrested in January for stabbing a neighbor. Neal’s mother said the neighbor was slightly cut after Neal grabbed a steak knife out of the hand of the neighbor who was threatening him with it.

That is a very high bail level for a supposedly minor altercation; the court clearly considered Neal to be a threat in some way. That, at least, was a correct evaluation; the neighbor victimized in that case was also one of Neal’s first victims yesterday. (Police discovered the body of Neal’s wife today, who was likely the very first victim.) Another clue might have been a history of mental illness, and the fact that he had a violent temper:

She said until recently Neal seemed content living in the rural neighborhood of modest homes and trailers and he grew marijuana on his property. Recently she said he began complaining about failing health he attributed to the nearby methamphetamine labs.

Neal’s sister, Sheridan Orr, said the family was trying to reach the sheriff’s department Tuesday evening but still had not been notified. She said her brother had struggled with mental illness throughout his life and at times had a violent temper.

“We’re stunned and we’re appalled that this is a person who has no business with firearms whatsoever,” Orr said. “Our deep, deep sympathy for the victims and it sounds trite but our hearts are breaking for them.”

A court agreed that he had no business owning guns; a restraining order in effect prohibited Neal from possessing firearms. And as CBS News reports, yet another signal was that he was “known to authorities,” and had been reportedly firing weapons at his neighbors for days:

Four people were killed in the assault that lasted 45 minutes and 10 more were injured, including at least one young student. Police killed the suspected shooter, Kevin Janson Neal.

They say he chose random targets and stole two vehicles during the rampage. Officers recovered one semi-automatic rifle and two handguns. One of the stolen vehicles, a white truck with bullet holes in the windshield, was removed from the area Tuesday night, reports CBS News correspondent Jamie Yuccas.

Neal was known to authorities and had at least one prior arrest. His neighbors had complained he had fired multiple rounds for days before this rampage that ended up at this elementary school.

It’s unclear from the reporting whether the neighbors reported the gunshots to police prior to Neal’s rampage. One would assume they did (if for no other reason than to keep from getting hit), but it might take a long investigation to put together a reliable timeline. If they did report the gunshots, what action did police take? How did a man out on $160,000 bail for a stabbing manage to elude supervision entirely? Shouldn’t the circumstances of that case have prompted authorities to investigate for mental illness and action to protect the community?

Another curious issue will be how and when Neal acquired his weapons. It’s not easy to buy and use firearms in California, which has one of the strictest gun-control regimes in the country, but it’s not impossible either. In this case, police say he acquired them “in an illegal manner,” and modified them to some extent.  Undoubtedly much of the policy focus after this rampage will be on tightening those restrictions even further, but if Neal got them illegally, that won’t do much to prevent what happened here. The issue appears more to be a lack of follow-through on dealing with a known threat and a failure to recognize a dangerous mental illness when it presented itself to authorities.

As bad as this was, it could have been worse — much worse. The local sheriff gives the school credit for an immediate decision to lock it down after Neal took shots at a parent outside the gates. While two students got injured in a six-minute barrage on its buildings from the outside, it would have been far, far worse had Neal managed to get inside the school. Kudos to the school for their quick action. Kudos also to the law-enforcement professionals who ended this rampage as soon as they did.