Lawyers for a survivor and relatives of nine who died filed papers Tuesday asking the state Supreme Court to hear their appeal.
A judge dismissed the lawsuit against Remington Arms in October, citing a federal law that shields gun manufacturers from most lawsuits over criminal use of their products.
Adam Lanza killed 20 first-graders and six educators with a Remington-made rifle. The lawsuit says the company should not have sold such a dangerous weapon to the public.
Remington's lawyers dispute the allegations and expect the appeal to be dismissed. Remington is owned by Madison, North Carolina-based Freedom Group.
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