BOSTON (AP) — Steward Health Care CEO Ralph de la Torre filed a lawsuit Monday against a U.S. Senate committee that pursued contempt charges against him for failing to appear before the panel despite being issued a subpoena.

The lawsuit, filed in federal court in Washington, named nearly all members of the Health, Education, Labor and Pensions Committee, including Sen. Bernie Sanders, who chairs the committee which has investigated Steward’s bankruptcy.

The lawsuit claims that the lawmakers are unlawfully violating de la Torre’s constitutional rights.

It alleges that the members of the committee, by trying to compel de la Torre to answer questions about Steward’s bankruptcy, are “collectively undertaking a concerted effort to punish Dr. de la Torre for invoking his Fifth Amendment right not to ‘be compelled . . . to be a witness against himself.’”

De la Torre is asking the court to declare that all actions related to enforcement of the subpoena are invalid and unconstitutional — including the vote of the committee on Sept. 19 approving the criminal contempt resolution and its decision to present the resolution to the full Senate for a vote.

The Senate approved the resolution last week.

“No one can be compelled to testify when they exercise this right under these circumstances. Nor does the Constitution permit Congress to punish and intimidate him, or any other American, for exercising these rights,” William “Bill” Burck, a lawyer for de la Torre, said in a statement.

Anna Bahr, communications director for Sanders, dismissed the lawsuit.

“Democrats and Republicans on the HELP Committee came together and unanimously voted to hold Dr. de la Torre in contempt of Congress, as did the entire U.S. Senate,” she said in a statement. “This case has no merit.”

The lawsuit comes a day before de la Torre is set to step down as CEO of Steward.

De la Torre has overseen Steward’s network of some 30 hospitals around the country. The Texas-based company’s troubled recent history has drawn scrutiny from elected officials in New England, where some of its hospitals are located.

A spokesperson for de la Torre said Saturday that he “has amicably separated from Steward on mutually agreeable terms” and “will continue to be a tireless advocate for the improvement of reimbursement rates for the underprivileged patient population.”

Sanders said earlier this month that Congress “will hold Dr. de la Torre accountable for his greed and for the damage he has caused to hospitals and patients throughout America.”

Steward has shut down pediatric wards in Massachusetts and Louisiana, closed neonatal units in Florida and Texas, and eliminated maternity services at a hospital in Florida.

Democratic Sen. Edward Markey of Massachusetts said that over the past decade, Steward, led by de la Torre, and its corporate enablers, “looted hospitals across the country for profit, and got rich through their greedy schemes.”

Alexander Merton, an attorney for de la Torre, has said the fault instead lies with “the systemic failures in Massachusetts’ health care system” and that the committee was trying to frame de la Torre as a criminal scapegoat. Merton has also said that de la Torre would agree to testify at a later date.

On Friday, Massachusetts Gov. Maura Healey announced her administration had formally seized a hospital through eminent domain to help keep it open and transition to a new owner. St. Elizabeth Medical Center in Boston was one of a group run by Steward. Operations will be transferred to Boston Medical Center.

Two other Steward-operated hospitals in Massachusetts were forced to close after qualified buyers could not be found during the bankruptcy process.