IANAL but it looks like the TSA partially self-owned here.
As the court document [0] points out, there exists a “law enforcement proviso,” which waives sovereign immunity for torts such as assault and battery committed by “investigative or law enforcement officers of the United States Government.” In other words, government cops can be sued for assault and battery. TSA said "our people aren't cops, so they can't be sued." The court said "Aha! You gave them badges! So they're cops!" (I'm oversimplifying -- the badges were just one piece of evidence the court cited).
Back in 2008, the TSA made a big deal about giving their people badges so they would be more respected by the public [1]. The court document even points this out and provides the [now dead] link to the press release. There was a bit of PR blowback then because most members of the public didn't think TSA screeners deserved badges. But the TSA insisted that they did, so now they have badges.
As the court document [0] points out, there exists a “law enforcement proviso,” which waives sovereign immunity for torts such as assault and battery committed by “investigative or law enforcement officers of the United States Government.” In other words, government cops can be sued for assault and battery. TSA said "our people aren't cops, so they can't be sued." The court said "Aha! You gave them badges! So they're cops!" (I'm oversimplifying -- the badges were just one piece of evidence the court cited).
Back in 2008, the TSA made a big deal about giving their people badges so they would be more respected by the public [1]. The court document even points this out and provides the [now dead] link to the press release. There was a bit of PR blowback then because most members of the public didn't think TSA screeners deserved badges. But the TSA insisted that they did, so now they have badges.
So that means they can be sued. Oops.
[0] https://cdn.ca9.uscourts.gov/datastore/opinions/2023/06/26/2...
[1] https://web.archive.org/web/20170429182331/https://www.tsa.g...