ANN ARBOR, MI - The University of Michigan has disciplined a professor who ignited controversy last month when he rescinded an offer of a recommendation letter for a student to study in Israel.

John Cheney-Lippold, an associate professor of American Culture at UM, is no longer eligible for a merit pay increase for the 2018-19 academic year.

The university has also frozen his sabbatical eligibility for two years, until the fall of 2020. Cheney had scheduled a sabbatical for the winter 2019 and will now have to wait until fall of 2020 to take it.

In an Oct. 3 letter from UM College of Literature, Sciences & Arts Interim Dean Elizabeth Cole said Cheney-Lippold's behavior "was inappropriate and will not be tolerated." The letter also mentions that "further conduct of this nature is subject to additional discipline, up to and including initiation of dismissal proceedings."

"In the future, a student's merit should be your primary guide for determining how and whether to provide a letter of recommendation. You are not to use student requests for recommendations as a platform to discuss your personal political beliefs," Cole wrote in the letter, which was obtained by The Ann Arbor News by the Freedom of Information Act.

Cheney-Lippold told the student in an email in September that he was taking part in an academic boycott against Israel, and could no longer provide the recommendation.

Cheney-Lippold said that after looking over the student's request, he needed to rescind his initial support, noting that "many university departments have pledged an academic boycott against Israel in support of Palestinians living in Palestine."

"I should have let you know earlier and for that I apologize," Cheney-Lippold wrote to the student. "But for reasons of these politics, I must rescind my offer to write your letter."

Cheney-Lippold told the student he would be available to write any other letters for the student in the email. He also later clarified in an email to The Ann Arbor News that he should have said "many university professors have pledged an academic boycott against Israel," rather than university departments.

In the letter outlining Cheney-Lippold's punishment, Cole noted that faculty are not required to write letters for every student who requests them for legitimate reason like a lack of time or information about the student, but that discretion is not unfettered.

"It does not extend to withholding a letter because of your personal views regarding the student's place of study and then using the student's request as a political platform to gain an audience for your own opinions, both in the media and in the classroom," Cole wrote.

News of Cheney-Lippold's punishment comes during an academic year that has seen the university receive scrutiny for campus incidents related to Israel.

The university was criticized by a senior Israeli cabinet minister, who sent a letter Monday to President Mark Schlissel over campus incidents that the politician described as showing a "vitriolic hatred against the Jewish state," according to the Associated Press.

Naftali Bennett, the minister responsible for education and diaspora affairs, admonished Schlissel over a lecture last week on the UM campus. In it, artist Emory Douglas shared his work, including a collage of side-by-side images of Israeli Prime Minister Benjamin Netanyahu and Adolf Hitler and the phrase "guilty of genocide" across their faces.

"The time has come for you as head of the University to make a strong stand against what has clearly become a trend of vitriolic hatred against the Jewish state on your campus," Bennett wrote to Schlissel.

Schlissel responded to the recent events surrounding the topic of personal beliefs, the responsibilities of educators and anti-Semitism in a message to the campus community on Tuesday co-authored by Provost Martin Philbert. He has called upon UM's provost to create a panel of distinguished faculty members to examine the intersection between political thought/ideology and faculty members' responsibilities to students.

"As we have stated, UM strongly opposes a boycott of Israeli academic institutions, and no school, college, department or unit at our university endorses such a boycott," the message states. "Our view is that educators at a public university have an obligation to support students' academic growth, and we expect anyone with instructional responsibilities to honor this fundamental university value. Our students deserve to be afforded all of the opportunities they have earned through their academic merit.

"We will work to make absolutely clear that faculty members' personal political beliefs cannot interfere with their obligations to our students with regard to letter-writing and all other modes of academic support."

Douglas was a longtime artist for the Black Panthers and much of the artwork highlighted during his lecture drew on themes of domestic racial and social injustice and oppression. Some of the works featured images and messages supportive of the boycott, divestment and sanctions movement against Israel, according to the AP.

The university said the Israeli leader's image in question was on a single slide among nearly 200 other slides not related to Israel that were presented over the course of an hour, adding that Douglas' work is critical of a wide range of world leaders, including several U.S. presidents.

"The Stamps program is intentionally provocative and the school is clear with students about this. The school does not control or censor what speakers present," the university noted in a statement regarding the lecture.

It noted in an introduction to the class that the menu of speakers was diverse and dynamic and "we do not control or censor what they say." It also informed students that "discovering what you do not agree with will help you find your voice as much or more perhaps than the things you find resonance with."

Michigan Hillel, which had also been critical of Cheney-Lippold's decision to rescind the letter of recommendation, also spoke out against the content of the lecture on a message on its website.

"Several weeks ago, we wrote to inform you of an incident with a professor refusing to provide a letter of recommendation for a student interested in studying abroad at an Israeli institution. We know for many of you, your concern regarding this incident was compounded last week by the news that a guest lecturer to the STAMPS program presented an offensive comparison equating Israeli Prime Minister Benjamin Netanyahu with Adolf Hitler," the message reads.

"We at Michigan Hillel share your concern that this image denigrated the memory of those killed in the Holocaust by suggesting a false equivalence to the Israeli-Palestinian conflict today."

The Washington Post reported Tuesday that a graduate student instructor declined to recommend a second student who was applying to a study-abroad program in Israel. The teaching assistant said her decision wasn't personal, but was born of a pledge to "boycott Israeli institutions as a way of showing solidarity with Palestine."

The Post reported that UM student Jake Secker had requested a letter of recommendation from graduate student instructor Lucy Peterson in hopes of studying abroad at Tel Aviv University this winter.

An email provided by Secker to the Post shows that Peterson initially agreed to write the recommendation before realizing she wouldn't be able to.

"I'm so sorry that I didn't ask before agreeing to write your recommendation letter, but I regrettably will not be able to write on your behalf," the email reads. "Along with numerous other academics in the US and elsewhere, I have pledged myself to a boycott of Israeli institutions as a way of showing solidarity with Palestine. Please know that this decision is not about you as a student or a person, and I would be happy to write a recommendation for you if you end up applying to other programs."

Since both Secker and Peterson are students at UM, the university said it is "precluded by federal law from discussing student matters."