There was something missing from Al Franken’s speech on Thursday.

Sen. Franken (D-MN) was resigning after multiple women reported that he had groped or otherwise sexually harassed them. He had apologized before, saying in a news conference just a few days ago, “I know that I’ve let a lot of people down.” Surely the speech announcing his resignation was a chance for him to show contrition before the Senate, the country, and, perhaps most importantly, the women who had risked public shaming to report their experiences with him.

But Franken did not take that chance. He did not apologize. Instead, he gave advice on running for office, focused on his own struggles rather than those of survivors, and seemed to take back the apologies he had already offered. In his speech, Franken squandered an opportunity to do good, and instead offered a master class in what not to do when accused of sexual misconduct.

Earlier this week, sociologist David Karp explained to Vox his five-point checklist for helpful public apologies: Specifically acknowledge the harm done, admit your role in it, express remorse, explain which behaviors you’ll stop in the future, and share your plan for making amends. Franken’s statement on Thursday failed on the very first step.

Franken said that in responding to women’s reports of his behavior, he “wanted to be respectful” of the broader conversation around harassment and men’s abuses of power. That decision, he said, may have given “some people the false impression that I was admitting to doing things that, in fact, I haven't done. Some of the allegations against me are simply not true. Others I remember very differently.”

Contrast that with Franken’s statement, at a news conference late last month, that, “there are some women, and one is too many, who feel that I have done something disrespectful that’s hurt them, and for that I am tremendously sorry.”

“I know that I am going to have to be much more conscious when in these circumstances,” he went on, “much more careful, much more sensitive, and that this will not happen again.”

As of Wednesday, eight women had publicly reported that Franken groped, kissed, or tried to kiss them without their consent. Several said he grabbed their butts or breasts during photo ops. Franken has specifically denied at least one of the allegations, and has responded less clearly, or not at all, to others, ABC News reports.

These are the possibilities: Franken was sincere in his apology in November, and is taking it back now to preserve some of his reputation. Or he was insincere and offered the apology as, in the best case, some sort of favor to the women involved or, in the worst case, an attempt to save his own skin. Either way, he has never offered the women who came forward the first thing they deserve: a clear explanation of what, if anything, he believes he did wrong and what, if anything, he is committed to changing.

Franken began his speech on Thursday by talking about the recent public discussion around sexual harassment. “We were finally beginning to listen to women about the ways in which men's actions affect them,” he said. “The moment was long overdue. I was excited for that conversation and hopeful that it would result in real change that made life better for women all across the country and in every part of our society.”

He had an opportunity, in his own speech, to contribute to that change. If he was in any way sincere in his previous apology, he could have been clear about his previous actions, expressed remorse, and explained what he would do differently. Instead, he talked about his own feelings, saying, “This has been a tough few weeks for me.” He offered his advice for those running for office, as though he were still a role model, cautioning that “there are a lot of long hours and late nights and hard lessons. And there is no guarantee that all your work and sacrifice will ever pay off.”

And most importantly, by offering a vague denial of the reports by his accusers, he encouraged voters to doubt and shame them. He gave ammunition to those who believe their accounts are part of a right-wing plot, and to the many who still think women who report harassment are vindictive harpies seeking to harm men.

Once Franken knew he would resign, he had a choice. He could do so in a way that helped a cause he claims to care about — protecting women from men’s abuses of power — or he could preserve some of his own reputation at the cost of harming that cause. He chose the latter. By going back on his earlier statements, he essentially took all of his accusers down with him.

Franken was right about one thing: It is unfair (though not, perhaps, “an irony,” as he put it) that he will leave the Senate and Roy Moore, who has been accused of sexually pursuing teenage girls, will probably enter it. It is unfair that he will resign and Donald Trump, who has been accused of harassment, assault, or other sexual misconduct by more than a dozen women, will remain the president. These are injustices that remain to be fought. But by sacrificing his accusers for the benefit of his own political legacy, Franken made it harder, not easier, to fight them.