The months-long scandal involving Senate President Stanley Rosenberg and his accused husband came to a head on Thursday when the Amherst Democrat bowed to pressure from his colleagues to resign, marking an ignominious end to a more than 30-year career in the Legislature that saw him rise to the heights of power on Beacon Hill.

Rosenberg, who in 2015 became the first openly gay leader of either branch of the Legislature, submitted his resignation on the heels of a damaging report released by the Senate Ethics Committee on Wednesday calling into question his leadership.

In a somewhat defiant statement, Rosenberg said he had hoped to return to work, but found he could not and still be "fair" to his constituents in light of the proposed discipline against him by his colleagues. Senate President Harriette Chandler, meanwhile, offered an apology on behalf of the entire Senate to victims of verbal and sexual harassment by Rosenberg's husband Bryon Hefner.

"As members of this body, we want to say to the victims, staff and all whose lives were affected, we are sorry for what you have been through. You deserve better. We must be better," Chandler said.

The Ethics Committee report, prepared by investigators with the law firm Hogan Lovells and accepted Thursday by the full Senate, found that Rosenberg failed in his responsibility to shield the Senate from his husband who he knew to be "volatile" and abusive to staff. He also gave his Hefner "unfettered" access to his official email and confidential Senate material on his computer, despite promising senators a "firewall" between his personal and professional lives.

While investigators found that Rosenberg did not violate any Senate rules, members of the Ethics Committee decided that he had demonstrated a "significant failure of judgment and leadership" by not doing more to intervene with his husband, who has also been indicted for sexually assaulting four men.

"We accept Senator Rosenberg's resignation because we agree with the decision that it is no longer appropriate for him to serve in the Senate," Chandler said at a brief press conference Thursday afternoon where she read from a prepared statement.

"It Would Not Be Fair"
Rosenberg turned in his resignation after taking the night to consider the Ethics Committee report, and seeing a number of his colleagues, including seven Democrats and one Republican, come out publicly and call for him to step down.

The 14-term senator, in a statement released after his resignation, highlighted the fact that investigators found "no conduct by me that violated Senate Rules or state ethics law, no evidence that Bryon influenced my actions as Senate president, and no knowledge on my part of any alleged sexual advances, assaults or attempts by Bryon to influence other senators or staff."

"I had hoped that, with the conclusion of the investigation, I would be able to focus, once again, on representing my constituents and contributing meaningfully to the work of the Senate," Rosenberg said. "In light, however, of the disciplinary measures recommended by the Ethics Committee, it would not be fair to my constituents to have a representative in the Senate who lacked the authority to represent their interests fully."

The committee, chaired by Sen. Michael Rodrigues of Westport, had recommended that Rosenberg be barred from returning to the president's office or serving in leadership or as a committee chair through the 2019-2020 session.

Some senators, however, suggested they wanted to see stronger discipline.

Sen. Jamie Eldridge, who called for Rosenberg to resign on Wednesday night, said at the very least Rosenberg should be suspended. In a statement, Sen. Kathleen O'Connor Ives also said that if Rosenberg had not resigned Thursday she would have supported suspension or explusion for Rosenberg.

"To do otherwise would be a slap in the face to every victim who provided information to the independent counsel, which helped form the report, and it would be a slap in the face to anyone still contemplating coming forward still," O'Connor Ives said.

Rosenberg, in his own one-page statement, said that he was not aware of many of the salacious incidents attributed to Hefner in the report, and took steps to address those that were brought to his attention.

"That does not diminish my sorrow at what reportedly transpired or my sense of responsibility for what the Ethics Committee concludes was a failure on my part in not doing more to protect the Senate," he said.

He also offered his "sincere apology" for the extent to which his efforts to intervene with Hefner fell short, and to the victims of Hefner's behavior.

Eldridge, who was once one of Rosenberg's staunchest allies in the chamber, said he found Rosenberg's comments to be lacking.

"I support Senator Stan Rosenberg's decision to resign, but I am disappointed that he still has not taken full responsibility for creating an environment that allowed his husband to harm so many people. I hope that he will take time to reflect on how his unacceptable actions and lack of accountability have damaged numerous lives and compromised the Massachusetts Senate," Eldridge said.

Rosenberg's decision to resign effective Friday at 5 p.m. lifted a burden from the shoulders of his soon-to-be former colleagues who had spent more than six hours behind closed doors over the course of two days digesting the report and debating how to respond.

"I think he made the right decision. I think the report made very clear that the conduct was inexcusable and it was going to be very hard to, in fact impossible to, continue in an effective way," Lesser said.

Senate Minority Leader Bruce Tarr, who sits on the Ethics Committee, said Rosenberg "absolutely" did the right thing for the Senate by resigning, saying the "right result here is to not have him continue to serve as a member of this body."

But Tarr said he and the Republican caucus were prepared to press for Rosenberg to be removed from the Senate if it became clear he did not plan to resign.

"I can speak for my caucus and we were prepared to take action. I don't want to be speculative. I would put it this way: we agree with the result that has ensued and we were prepared to get to that place one way or another," Tarr said.

Asked why he would endorse the more limited recommendations of the Ethics Committee, Tarr said Senate Republicans agreed with the report's findings and wanted to give Rosenberg a chance to step aside on his own before pushing the Senate to remove him.

"That is an action that should only be used in the rarest of instances and it should be done primarily by the voters who send someone here to represent them," Tarr said outside the Senate president's office. "That being said, we were willing to give Senator Rosenberg the opportunity to do the right thing. He did it."

Gov. Charlie Baker, who was also among the first on Wednesday to say Rosenberg should not remain in office, said he was pleased with the outcome on Thursday in light of the "incredibly disturbing" details laid out in the Hogan Lovells report.

"I'm glad that he did. I think he made the right decision," Baker said.

"This Is a Tragedy"
Rosenberg worked as chair of the Senate budget committee in the 1990s at the same time Baker led Gov. William Weld's budget office, and the two have met regularly and worked together over his three-plus years in office.

"I have always appreciated the opportunity to work with him. We may not always agree, but there was a lot of respect there and I appreciated that too. But in this particular instance, I think that report made pretty clear that there was damage done to the institution and to the Senate and I think it was appropriate for him to step down," the governor said.

The respect for Rosenberg, even at a low point in his career, was not confined to the governor. Tarr called Rosenberg "one of the most affable and personable Senate presidents in recent memory."

Arline Isaacson, co-chair of the Massachusetts Gay and Lesbian Political Caucus, also lamented what she described as a "blemish" on an otherwise impressive resume.

"He's been an incredibly strong advocate for the LGBT community, for education K-12 and higher ed, and for progressive politics across the board, and he was known for being hard working, thoughtful, caring and fair -- what you'd want a legislator to be. This is a tragedy and a real loss for the LGBT community and for progressives," Isaacson said.

Rosenberg, over his 27-year career in the Senate, helped champion gay marriage, oversaw the last redistricting effort, spearheaded the push for the recent criminal justice bill and helped write the law that brought casino gambling to Massachusetts. He has also been a strong advocate for the University of Massachusetts.

The conclusions drawn by investigators over the course of a five-month investigation, however, proved too much for even those senators close to him.

"The reality is that there's some very damning things in the report and beyond challenging things in the report, things I think are very difficult for many of us to even deal with so at this point it's my opinion that political expediency and loyalty, when you're talking about sexual assault and serious crimes like this, all that gets thrown out the window," Sen. James Welch, of West Springfield, said Thursday morning.

Welch, who was one of the seven Democrats who called on Rosenberg to resign, said, "My main goal today is to further continue to protect and advocate on behalf of the victims and further protect and advocate on behalf of the institution of the Senate."

Sen. Barbara L'Italien, who called for Rosenberg's resignation, said the former Senate president could have made things easier on Hefner's victims had he resigned earlier. An Andover Democrat who is running for Congress, L'Italien said she spoke to Rosenberg about his position in the Senate late last year after news of Hefner's alleged behavior broke, but has not spoken to him recently.

"I do believe a few people called him. I personally did not," L'Italien said.

Sen. Michael Barrett, a Lexington Democrat, declined to say whether he has spoken to Rosenberg about resigning.

"I think overall today's outcome reflected the will of the rest of the Senate," Barrett told the News Service. He said, "The report is very graphic and filled with facts that none of us knew previously."

Senate Ethics Committee Chairman Michael Rodrigues and Sens. Eric Lesser, Julian Cyr and Cindy Friedman all said that they had not spoken to Rosenberg about resigning before Rosenberg made the decision.

Colin A. Young and Andy Metzger contributed reporting.