The U.S. Supreme Court debated the reach of airlines’ legal immunity when they report potential security threats, as the justices heard the case of a pilot upset about losing his job.

The justices on Monday reviewed a $1.4 million award won by the pilot, William L. Hoeper, who sued Air Wisconsin Airlines Corp. for telling federal officials as he was preparing to board a flight as a ­passenger that he was “unstable” and possibly armed.

Several justices suggested they were loath to let juries second-guess the split-second decisions made by ticket agents, baggage handlers and flight attendants. That prospect “doesn’t give me a lot of comfort,” Justice Antonin Scalia said.

Airlines say a Colorado Supreme Court ruling that upheld the award leaves them legally vulnerable when they follow instructions from the Transportation Security Administration, which tells carriers to err on the side of reporting security issues. The Obama administration is backing the industry in the case.

Eden Prairie attorney Donald Chance Mark Jr. is on the legal team representing Air Wisconsin Airlines.

Bloomberg News Service