In a 29-page decision, Connecticut Superior Court Judge Robin Wilson granted the town's request for summary judgment saying the school officials' actions were protected by governmental immunity.
The case was filed by the parents of slain students Jesse Lewis and Noah Pozner.
The suit claimed that school officials didn't follow security rules by not immediately ordering a lockdown of the school when Adam Lanza entered the school shooting and claimed that staff was not trained for such an emergency.
It also claimed that classroom doors could only be locked from the outside and that teachers did not have keys to lock the doors.
In the decision, Wilson likened the teachers and administrators to police officers who have to make split-second decisions in emergencies: “Emergencies, by their very nature, are sudden and often rapidly evolving events, and a response can never be 100 percent scripted and directed,” she said.
Lanza shot and killed 20 first-graders and six adults after killing his mother, Nancy Lanza on Dec. 14, 2012.
He entered the school by shooting through a window next to the locked front door.
An attorney for the two families said they plan to appeal within the 20-day time limit.
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