Waterford — It’s not every day that a lawyer puts the brakes on the sovereign immunity that Indian tribes enjoy.

But that’s the kind of day James Harrington had Tuesday.

Harrington, of Polito & Associates, the two-lawyer firm with offices in the Waterford Professional Complex on Vauxhall Street Extension, learned around 10 a.m. that his side had prevailed in the potentially landmark case he’d brought to the U.S. Supreme Court last year.

In an 8-0 vote, the court ruled that an Indian tribe’s sovereign immunity from lawsuits does not extend to a tribal employee sued over actions he took within the scope of his employment if he’s sued as an individual rather than as an employee of the tribe.

“The employee, not the tribe, is the real party in interest and the tribe’s sovereign immunity is not implicated,” Justice Sonia Sotomayor wrote in the court's 12-page opinion.

Chief Justice John Roberts and Justices Anthony Kennedy, Stephen Breyer, Samuel Alito and Elena Kagan joined Sotomayor’s opinion. Justices Clarence Thomas and Ruth Bader Ginsburg filed concurring opinions. Justice Neil Gorsuch, newly sworn in this month, took no part in deciding the case.

For Harrington and his clients, a Pennsylvania couple injured in a 2011 car crash involving a Mohegan Sun limousine, the decision couldn’t have been any better. It reversed the Connecticut Supreme Court decision they had appealed and sends the case back to New London Superior Court, where it’s expected to proceed on its merits.

“I’m very pleased,” Harrington said in an interview. “The court adopted the argument we made to the Connecticut Supreme Court. Sometimes, they will try to introduce another argument, but they didn’t. The other side raised something else, the concept of ‘official immunity,’ but the court didn’t even address it."

“It’s really a full-throated endorsement of the arguments we were making,” Harrington said.

Humbert Polito Jr. credited his associate with recognizing the potential significance of the case and relying on arguments that had never been made before in Connecticut courts, arguments that Superior Court Judge Leeland Cole-Chu had accepted.

“If not for the excellent lawyering James provided, we wouldn’t be here today,” Polito said.

Harrington originally filed the case, Lewis v. Clarke, in 2013 in New London. In it, Brian and Michelle Lewis of Bethlehem, Pa., claimed that the negligence of the limousine driver, William Clarke of Norwich, caused the accident that left them seriously injured. Clarke’s vehicle rear-ended the Lewises’ vehicle on Interstate 95 in Norwalk.

Clarke was an employee of the Mohegan Tribal Gaming Authority, which operates Mohegan Sun.

In their concurring opinions, Thomas wrote that Clarke could not assert immunity because the Lewises' suit arose from "an off-reservation commercial act," while Ginsburg sided with dissenting opinions in other cases that "explain why tribes, interacting with nontribal members outside reservation boundaries, should be subject to non-discriminatory state laws of general application."

Asked to comment on the U.S. Supreme Court decision, a Mohegan tribal spokeswoman issued a statement attributed to attorneys for the tribe: “The Mohegan Tribe is proud to have defended its right — one shared with the Federal Government, state governments, and foreign governments, and recognized by the State of Connecticut in a Tribal-State compact — to channel suits against its own employees to its own judicial system. Although the Supreme Court did not agree with the reasoning of the Connecticut Supreme Court, we are heartened that it left open the possibility that other legal principles may nonetheless require this suit against Mr. Clarke, a former employee of the Mohegan Tribe, to proceed in tribal court.

"We will continue to work to ensure that claims against the Tribe’s employees are brought in a fair, equitable, and appropriate forum.”

Harrington also represented two Fairfield County couples who were riding in the limousine, which was taking them home from the casino. All of the limousine passengers were injured and all sued Mohegan Sun — not Clarke individually — in the Mohegan Gaming Disputes Court. All of them settled their claims.

Harrington recalled Tuesday that attorneys for Clarke filed a motion to dismiss the Lewises’ suit before any discovery in the case could take place.

After Cole-Chu denied Clarke’s motion, the Connecticut Supreme Court agreed to hear the case. In a March 2016 decision, it overturned Cole-Chu’s ruling, finding that the Mohegans’ sovereign immunity did bar the suit.

Harrington then petitioned the U.S. Supreme Court, which agrees to hear about 1 percent of the thousands of petitions it receives each year. In September, the high court announced it would take the case.

On Jan. 9, Harrington’s co-counsel, Eric Miller of the Perkins Coie firm’s Seattle office, argued the case before the eight sitting justices. A lawyer for the U.S. Office of the Solicitor General also argued for reversal of the Connecticut Supreme Court decision, while Neal Katyal of the Washington, D.C., firm Hogan Lovells argued for Clarke and the Mohegan Tribe. Katyal is a former acting U.S. solicitor general.

Harrington said his clients deserve credit for seeing the case through to its conclusion. He said they resisted the tribe’s offers to settle, including before and after the U.S. Supreme Court heard the case.

“They understood it could have an effect that goes far beyond them,” he said. “It could have ramifications around the country.”

b.hallenbeck@theday.com