The opera superstar Plácido Domingo, whose five-decade American career was sidelined last year by allegations of sexual misconduct, “engaged in inappropriate activity, ranging from flirtation to sexual advances, in and outside of the workplace,” an investigation by a performers’ union found.
The release on Tuesday of the findings of the union, the American Guild of Musical Artists, prompted Mr. Domingo, 79, a famed tenor who held leadership positions at the Los Angeles Opera and the Washington National Opera, to issue his fullest apology yet.
“I have taken time over the last several months to reflect on the allegations that various colleagues of mine have made against me,” Mr. Domingo said in a statement. “I respect that these women finally felt comfortable enough to speak out, and I want them to know that I am truly sorry for the hurt that I caused them.”
“I accept full responsibility for my actions, and I have grown from this experience,” he continued. “I understand now that some women may have feared expressing themselves honestly because of a concern that their careers would be adversely affected if they did so. While that was never my intention, no one should ever be made to feel that way.”
The inquiry began after The Associated Press reported last summer that more than 20 women had accused Mr. Domingo of sexual harassment or inappropriate behavior dating back to the late-1980s. Most were not named.
Several American companies, including the Metropolitan Opera and the San Francisco Opera, canceled Mr. Domingo’s appearances following the allegations. But European companies said they would await the outcome of investigations into his behavior before acting. It was not immediately clear how they would respond to the union’s findings.
Next month, Mr. Domingo is scheduled to sing the title role in Verdi’s “Simon Boccanegra” at the Hamburg State Opera. A spokesman for the company, Michael Bellgardt, said in an email on Tuesday that he expected Mr. Domingo to perform as planned “if nothing happens to call this into question.”
Mr. Domingo also has upcoming performances planned at the Bolshoi in Moscow, the Teatro Real in Madrid, the Vienna State Opera, the Royal Opera House in London and Teatro alla Scala in Milan, among others. “Placido will be here in the summer performing as planned in Don Carlo,” Vicky Kington, a spokeswoman for the Royal Opera House, said in an email on Tuesday, when asked if the union’s findings would affect his appearance.
The full details of the investigation commissioned by the American Guild of Musical Artists, which represents opera soloists, choristers, choral singers, actors, ballet dancers and production staff, were not immediately released. But its conclusions were.
“The investigation concluded that Mr. Domingo had, in fact, engaged in inappropriate activity, ranging from flirtation to sexual advances, in and outside of the workplace,” it said in a statement. “Many of the witnesses expressed fear of retaliation in the industry as their reason for not coming forward sooner.”
Raymond Menard, the union president, said in a statement that the union would “remain committed to confronting systemic problems which can cause our members to suffer unlawful discrimination and harassment at work, and to protecting the health and safety of our members.”
The Los Angeles Opera, which Mr. Domingo helped found, and led until he stepped down last year, is still conducting its own investigation.
Alex Marshall contributed reporting.