Story highlights Protection of Lawful Commerce in Arms Act provides immunity to gunmaker, judge says

Adam Lanza killed 20 children, six teachers at Sandy Hook Elementary on December 14, 2012

(CNN) A Connecticut judge has dismissed a lawsuit that families of the Sandy Hook Elementary School shooting victims had filed against a gun manufacturer.

In her decision granting the company's motion to strike the case, Superior Court Judge Barbara Bellis invoked a federal statute known as PLCAA , the Protection of Lawful Commerce in Arms Act.

The law prohibits lawsuits against gun manufacturers and distributors if their firearms were used in the commission of a criminal act.

The families had sought an exemption through a claim of "negligent entrustment," arguing the maker knowingly marketed and sold the Bushmaster AR-15 rifle to civilians despite knowing it posed a risk when used outside "highly regulated institutions" such as law enforcement or the military. Remington is the parent company of Bushmaster.

Bellis said the "criminal misuse of a weapon" by Adam Lanza means the action "falls squarely within the broad immunity provided by PLCAA," adding that the arguments presented by the families do not fit within the definition of negligent entrustment.

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