WASHINGTON — The House Ethics Committee said Wednesday it will open an investigation into Rep. Tony Gonzales, R-Texas, who is accused of having had an affair with a staffer before she died by suicide last year.

Gonzales exchanged sexual texts in 2024 with his then-aide, Regina Santos-Aviles, according to messages previously obtained by NBC News and verified by her widower, Adrian Aviles. Gonzales initially denied having had an affair with Santos-Aviles and refused to address the substance of the allegations after the texts came to light.

It is against House rules for lawmakers to engage in relationships with their staff members.

Later Wednesday, Gonzales appeared to acknowledge the affair when he was asked on the “Joe Pags Show” podcast whether he had a relationship “with this young lady who was working in your office.”

“I made a mistake, and I had a lapse in judgment. And there was a lack of faith, and I take full responsibility for those actions,” Gonzales said, adding that he has “reconciled” with his wife.

The Ethics Committee’s chair and ranking member said in a statement Wednesday, “Pursuant to the Committee’s action, at this time, the Investigative Subcommittee shall have jurisdiction to determine whether Representative Tony Gonzales violated the Code of Official Conduct or any law, rule, regulation, or other applicable standard of conduct in the performance of his duties or the discharge of his responsibilities,” with respect to allegations that he engaged in sexual misconduct or engaged in favoritism.

Gonzales responded to the announcement, “I welcome the opportunity to present all the facts to the committee.”

In the podcast interview, he said, “I appreciate the opportunity to be able to provide all the facts and all the details that lead to exactly what occurred in the entire situation.”

The bipartisan panel said it will select and announce which lawmakers will serve on the investigatory subcommittee.

In addition to the ethics probe, the Office of Congressional Conduct carried out an inquiry into Gonzales, the results of which will be delivered to the Ethics Committee on Wednesday. The office had been prohibited from sending the report to the committee earlier because it was completed within 60 days of the Texas primary Gonzales participated in Tuesday.

Gonzales failed to earn 50% of the vote in that race, forcing him into a runoff against Republican challenger Brandon Herrera. Herrera narrowly led Gonzales in the initial primary vote Wednesday. Gonzales beat Herrera by only a few hundred votes in a similar 2024 runoff.

It is not clear whether the Ethics Committee’s investigation will wrap up before the runoff, scheduled for May 26. The committee’s rules say that it must address an Office of Congressional Conduct report within 45 days of receipt but that it may postpone reporting if it falls within the 60-day window before a pertinent election.

A formal investigation into Gonzales does not necessarily mean the committee’s final report will be made public. The committee has jurisdiction only over sitting members of Congress, so if Gonzales resigns or is voted out of office before the report is complete, the investigation could come to a halt.

Several of Gonzales’ Republican colleagues have urged him to resign or end his campaign, including Reps. Lauren Boebert of Colorado, Nancy Mace of South Carolina and Brandon Gill of Texas. Rep. Anna Paulina Luna of Florida called the text messages “disgusting” but has stopped short of calling for his resignation.

Gonzales said last month that he would not resign over the allegations.

Mace forced a floor vote Wednesday on a resolution that would direct the Ethics Committee to make public all reports on allegations of sexual misconduct or harassment by congressional lawmakers or aides. The House voted to refer Mace’s resolution to committee, effectively killing it.