Cogan cites an announcement by another health insurance provider, Anthem Blue Cross Blue Shield, that it would limit reimbursement for anesthesia during surgery and other medical procedures in Connecticut, Missouri and New York. The company's Nov. 1 announcement drew widespread criticism from anesthesiologists and politicians. But on Dec. 5, the day after Thompson's killing, Anthem said it was withdrawing the policy change.

Cogan said that before the anesthesia policy was retracted, he saw social media posts referencing the policy along with the home address of Anthem's CEO and her photo.

"Was this due to the uproar about denying claims? I don't know," Cogan said. "But if it was, here's what I think is going to happen: Anthem is going to reassert this policy in six months, or, if they think they are losing money, they'll figure out another way to address whatever issue they have. My speculation is that Anthem may have reacted, but it's not going to be long-term."

And the same goes for the way United and other health insurance companies approach litigation by hospitals and doctors. These companies are accustomed to being unpopular with the public, and the killing of Thompson won't result in any big changes to their litigation strategy, Cogan said.

"These companies don't care that much about what people think," Cogan said. "Really harsh thing to say. There's not going to be a change in their behavior because of this. And as far as public sympathy or public reaction to the bad behavior of insurers, it may get a little traction. I suspect that Anthem retracted its policy, at least in part, because of what happened to the CEO of United. But at the end of the day, these are for-profit companies. They're very good at making money, and I don't think it's going to change their behavior. And I think any sort of publicity effects will wear out over time. I think the extent to which it affects any litigation may be short-lived."

Some people reacted to the shooting of Thompson by saying he was a killer because he was denying claims and people were dying as a result, but the "moral equivalence" there is not the same as a person being shot in the street, Cogan said. But Thompson and the people who deny claims for medical treatment are not in the hospital room or looking face-to-face at the patient whose claim they deny, he said.

"There's a long sort of psychological distance between what this guy was doing and what all the United people are doing, and their effect on people. They don't see it. And I think that has an effect on the way insurance companies operate," he said.

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UnitedHealthcare and its parent company, UnitedHealth, removed a flurry of contract cases to federal court in the last week. The company removed at least 12 breach-of-contract lawsuits from state court to federal courts in Alabama, New Jersey and New York, all of which seek reimbursement for medical services rendered.

In Alabama, King & Spalding brought two suits against UnitedHealthcare over its failure to reimburse hospitals at the allowable rate for drugs administered to Medicare patients. A suit on behalf of three hospitals in Montgomery, Alabama, was removed to the U.S. District Court for the Middle District of Alabama on Dec. 2, and another suit on behalf of the University of Alabama Hospital was removed to the U.S. District Court for the Northern District of Alabama on Dec. 6.

The Alabama suits claim UnitedHealthcare continues to violate a 2022 U.S. Supreme Court ruling, American Hospital Association v. Becerra, which said that a federal policy reducing certain drug reimbursements violates the Medicare act and frustrates a law intended to ensure that hospitals serving low-income patients, including the plaintiffs, are adequately subsidized.

UnitedHealthcare removed seven cases to the U.S. District Court for the District of New Jersey between Dec. 2 and Dec. 5. All were brought by Maggs, McDermott & DiCicco of Wall, New Jersey, on behalf of The Plastic Surgery Center of Shrewsbury, New Jersey. In each of the cases, the plaintiff, which is an out-of-network provider for UnitedHealthcare, says the company went back on agreements to pay the in-network rate for performing breast reconstruction surgery on patents who had undergone mastectomies due to breast cancer. Robinson & Cole in New York represents UnitedHealthcare in those cases.

In addition, UnitedHealthcare removed three cases to the U.S. District Court for the Eastern District of New York on Dec. 4 and 5 on behalf of neurologist Jeffrey Farkas. Farkas, represented by Gottlieb & Greenspan of Fair Lawn, New Jersey, claims he performed various procedures after United promised to reimburse those charges based on the plaintiff's billed charges or an amount that was agreed on between the doctor and United, so that the patient would be held harmless for the remainder. Robinson & Cole represents UnitedHealthcare in the New York cases.