It's not the board's fault per se, a lot of parents absolutely do not want their children to be exposed to the trappings involved in a hardened environment. I have heard parents state they don't want their children seeing people walking around carrying guns, having to go through metal detectors, or having their "innocence stolen" by them having to understand that there are evil people in the world that could mean them harm but there are things that they can do to help reduce the possibility that they too become a victim, even things they can learn to do to protect themselves and survive if their school should ever become a target.
As far as holding the district and their security personnel liable for any loss of life or injuries, security measures are all about mitigation of risk, nothing and no one can absolutely guarantee no harm will occur. Having said that though, if your personnel follow establish security procedures as they were trained to do and do all within their power to stop a threat then no, there should be no prosecution in my opinion.
If they didn't do what they were supposed to that's a different story.
I know that having someone on-site along with other security hardening measures can definitely mitigate the risk to the students from an OUTSIDE threat, however they will not eliminate the threat from someone thoroughly dedicated to inflict as much harm as possible like the Buffalo shooter who was confronted and shot 11 times it was reported by a retired police officer working security at the Top's grocery store. The 11 shots were ineffective because the shooter was wearing Kevlar and I still haven't seen anything indicating from where he obtained it, because it's not sold to the general population.
Lastly, I hated the way school resource officer Scott Petersen was treated because he didn't go into the building to confront school shooter Nikolas Cruz during the Parkland school shooting at Marjorie Stoneman Douglas high school back in 2018. Petersen at least tried to get Cruz involuntarily committed (Baker Act) but there were so many people trying to keep Cruz's criminal history clean that it is alleged that they refused to allow him to be committed. Had they no interfered, Cruz possibly could have been locked up somewhere instead of free to kill more than a dozen of his classmates.
'They Don't Know The Truth': Ex-School Resource Officer Scot Peterson Defends Actions During Parkland School Shooting
Worse still, now we find out after the horror of the elementary school shooting in Uvalde, Texas earlier this week, that the police waited an hour before entering the school to confront the 18 year old shooter Salvador Ramos, in spite of the huge number of law enforcement officers and agents who responded to the scene.
