The student organizers of a Yale Law School conference have rescinded their invitation for Philadelphia District Attorney Larry Krasner to serve as keynote speaker, citing his decision to appeal a judge’s ruling in favor of convicted cop killer Mumia Abu-Jamal.

A judge ruled in December that Abu-Jamal could reargue an appeal before the Pennsylvania Supreme Court, and Krasner’s office appealed that ruling Jan. 25.

Krasner was to be one of four keynote speakers later this month at the Rebellious Lawyering (RebLaw) conference, which is described on the group website as a forum to “discuss innovative, progressive approaches to law and social change.”

“We cannot understand how DA Krasner’s decision in this case serves justice or the transformative vision that he ran on,” organizers wrote in a letter made public Friday night. “We also hear and deeply appreciate the voices of ... law students and activists calling on us to take action in response.”

In addition to withdrawing Krasner’s slot as keynote speaker, the organizers also urged the district attorney to drop his appeal of the December decision by Common Pleas Court Judge Leon Tucker. The judge ruled that Abu-Jamal should be allowed to reargue his appeal because then-Chief Justice Ronald D. Castille, a former Philadelphia district attorney, did not recuse himself when Abu-Jamal’s case came before the court.

Tucker, however, rejected the claim that Castille had “personal significant involvement” in his case while Castille was in the District Attorney’s Office from 1986 to 1991.

Krasner spokesperson Ben Waxman said Saturday that the District Attorney’s Office had made its decision with great care.

“We wish the student organizers a successful event and respect their passion," Waxman said. He said the DA’s Office is "also passionate about making carefully considered decisions that are based on the law and facts of every case. That is what we are doing now on the evolving issues in the case of Mumia Abu-Jamal and the cases of thousands of less well-known defendants. As with all legal decisions, some people will disagree, but that’s not going to change what we do.”

In their letter, RebLaw representatives said they had given Krasner the option instead to “join activists in a conversation about the promise and perils of ‘progressive prosecution,' including directly discussing his decision to appeal Mumia’s court decision. The DA declined to take part in such a conversation.”

Abu-Jamal, 64, a former Black Panther and sometime radio reporter, is serving a life sentence for the Dec. 9, 1981, shooting death of Philadelphia Police Officer Daniel Faulkner, who was 25 when he was gunned down at 13th and Locust Streets.

The decision to withdraw Krasner’s invitation was prompted in part by concerns from Harvard Law students who plan to attend the conference.

One of them, anneke dunbar-gronke, acknowledged in a phone interview that Krasner was known for “progressive prosecution."

But she said his actions in the Abu-Jamal case were at odds with the conference’s name. “If you’re a prosecutor who is putting people in cages, that’s just not rebellious lawyering,” she said.

Judith Ritter, an attorney for Abu-Jamal, did not respond to a request for comment.

A previous version of this article incorrectly stated that conference organizers had invited Abu-Jamal to replace Krasner as keynote speaker.