NEWTOWN, Conn. (CBSNewYork/AP) – The Newtown families who lost their children in the Sandy Hook Elementary School massacre are asking the Connecticut Supreme Court to reconsider their lawsuit to hold the gun maker responsible.

A lower court threw out their case last year. 

READ MORE: Drug Trafficking Ring Shipped Cocaine To New York Inside Children's Lunch Boxes, Investigators Say

“We have not lost one ounce of confidence in the justness in our case,” said Ian Hockley, who lost his son, Dylan.

On Dec. 14, 2012, Adam Lanza, 20, shot and killed 20 first-graders and six educators at Newtown, Connecticut school, before turning the gun on himself. Lanza also killed his mother before the school shooting.

In Memoriam: The Victims Of The Sandy Hook Elementary School Shooting

The attorney for the 10 families, Josh Koskoff, argued the gun maker can be held responsible under a legal concept called “negligent entrustment,” which applies when the supplier knows, or should know, the user is likely to harm others, WCBS 880’s Alex Silverman reported.

READ MORE: Nonprofits Now Have New Home In Brooklyn, Thanks To Transformation Of Bedford-Union Armory

“Remington may have never known Adam Lanza, but they had been courting him for years,” Koskoff said.

Photos: Shooting At Sandy Hook Elementary School In Newtown, Conn.

The company’s lawyer, James Vogts, argued otherwise.

“The manufacturer – one and two steps removed – has no opportunity to assess that buyer,” he said.

Lanza’s mother, Nancy, legally bought the rifle and often went to a shooting range with her son, who had mental health issues, authorities have said.

The case is being watched by gun rights supporters and gun control advocates across the country as one that could set a precedent in cases accusing gun-makers of being responsible for mass shootings. Several groups including the National Rifle Association and emergency room doctors submitted briefs to the court.

MORE NEWS: Candidate Conversations: Curtis Sliwa

(© Copyright 2017 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)