(AP) — An unprecedented legal move by MGM Resorts International to sue surviving victims of the Las Vegas mass shooting took another unusual turn Tuesday when the casino-operator offered to make $500 charitable donations for each person who waives or has their lawyer accept legal notice of the lawsuits.

The move is part of MGM’s attempt to have a federal judge hear the cases and declare that the casino-operator has no liability for the mass shooting at one of its properties under a law enacted after the Sept. 11 terrorist attacks.

The federal law cited by MGM limits damages against entities that implement security measures approved by federal officials.

MGM has insisted its lawsuits, which don’t demand money, are meant to avoid years of costly litigation.

However, attorney Robert Eglet, part of a group representing victims, said MGM is just trying to “spin” its attempt to save money on serving legal notices.

“This is just more outrageous conduct by them,” Eglet said.

The mass shooting occurred Oct. 1 at an outdoor music festival when a high-stakes gambler opened fire on the venue from the 32nd floor of the Mandalay Bay casino-resort, killing 58 people and injuring more than 800 others.

Twenty-two thousand people were at the festival during the shooting. The company sued more than 1,900 of them in July and has been working to notify them of the lawsuits.

As part of the offer, each victim would choose a charity that supports survivors or families of slain victims, and the donation would be made in his or her name. MGM could end up donating close to a $1 million if everyone took its offer.

MGM says it would rather make the donations to charities than spend the money to pay people to serve the legal notices.

“The money spent on personal service of process — up to $250 per person — could be better directed to do some affirmative good,” MGM’s attorneys wrote in the letter shared with The Associated Press.

If the offers are not accepted, “we will personally serve the complaints courteously and respectfully,” MGM spokeswoman Debra DeShong said.

The defendants are people who previously sued the company and voluntarily dismissed their claims and those who have threatened to sue, according to the lawsuits filed by MGM.

The company has cited a 2002 federal law that limits liability when a company or group uses services certified by the U.S. Department of Homeland Security. MGM argues that the security vendor for the outdoor venue in Las Vegas was federally certified at the time of the attack.

Eglet said his firm and others working together represent all but six of the 1,977 people who were sued and who might want to file claims against MGM in state court.

He said the group does not represent the people against the complaints filed by MGM and has not been authorized to accept the legal notices.