When 20-year-old Adam Lanza walked into Sandy Hook Elementary — the same school he attended as a child — he was carrying a few guns, but his main one was a Bushmaster AR-15 rifle.
In a span of a few minutes, 20 students and six educators were dead. In one classroom, police recovered 80 expended bullet casings from the gun. In another, 49.
"How does a kid around the corner get his hands on a weapon that was designed for killing large amounts of people in a short amount of time on the battlefield?" asked Mark Barden.
Barden's 7-year-old son, Daniel, was killed at Sandy Hook. Now, Barden is one of 10 plaintiffs suing Remington Arms Co., the manufacturer of the assault rifle used in the mass murder, along with the gun's distributor and seller.
On Monday, a judge will hear arguments about whether the case has legal merit to proceed to trial. That decision is expected to take months.
The plaintiffs argue that the AR-15, a modified version of a gun used by the military in Vietnam, never should have been marketed and sold to civilians.
"Now it wasn't meant to be designed to kill innocent civilians, but the weapon doesn't know that," said Josh Koskoff, a lawyer representing the Sandy Hook victims. "And so arming civilians with a weapon whose specific use is to kill people — when gun companies know that people kill people — is negligent."
But Remington said that's not the case.
The company and its lawyers didn't respond to requests for comment, but a recent motion it filed says the assault rifle used at Sandy Hook was lawfully sold and purchased by the shooter's mother. And it says the Protection of Lawful Commerce in Arms Act, passed in 2005, protects the manufacturer.
"Car manufacturers don't get this kind of immunity," said John Thomas, a professor of law and public health at Quinnipiac University. "Knife manufacturers don't get this kind of immunity — lawn mower manufacturers don't. But Congress decided to immunize gun manufacturers and dealers from lawsuits based on acts committed with their products."
But Thomas said there is an exception to the immunity law. It's something lawyers call "negligent entrustment" — basically, selling or "entrusting" a gun to a suspicious buyer who plans to commit a crime with it.
Thomas said prior court cases challenging the 2005 law generally focused on acts of negligence in particular sales to individual customers.
"But the plaintiffs in the Sandy Hook case have a creative spin on it, and they say it's actually negligent to sell to civilians any weapon like an AR-15, an assault rifle, because it's designed not for target shooting or carrying in your purse to protect yourself in a dark parking lot, but it's designed for military use," Thomas said.
Attorney Katherine Whitney said Remington will challenge that assertion. She previously represented a retailer that sold to the person who opened fire at a movie theater in Aurora, Colo.
"Their argument is, 'Hey we're not a seller. Because we're not a seller, this negligent entrustment exception doesn't apply,' " Whitney said.
Still, the case has made progress. In April, a judge decided there was jurisdiction to allow the case to proceed in a Connecticut court.
The judge also opened up the process of evidence discovery, which means plaintiffs are optimistic they'll soon access AR-15 marketing materials and interview company executives at Remington.