A retired professor from the University of Southern Maine has been “barred” from teaching at any of the school’s campuses after offering an unauthorized “pop-up” class for students to protest against the confirmation of then-Supreme Court Nominee Brett Kavanaugh.

President Glenn Cummings announced the university’s decision regarding Dr. Susan Feiner Wednesday after learning that she offered students a course that would bus them to Washington to demonstrate against Sen. Susan Collins, R- Maine, who supported the confirmation of Kavanaugh, the Portland Press Herald reported.

“We are embarrassed by and apologize for the rogue behavior of a former colleague,” Cummings said in a statement obtained by the newspaper.

“In response to her inappropriate actions, Dr. Susan Feiner has been notified that she is now barred from teaching at the University of Southern Maine, a prohibition that will be upheld by the other campuses of the University of Maine system as well.”

The university said that the one-credit course was arranged without knowledge or consent and that no school funds were used to support the trip.

Cummings said in his statement that Feiner used the “unauthorized” course as a way to advance her “personal political agenda.”

University spokesman Robert Stein said that "as far as we know," no students participated in the bus trip to D.C. "If any students went, it was without credit and on their own," he said.

Feiner said in a text message to the Press Herald that she would not challenge the school’s ruling because she is “retired.”

“It’s USM’s loss,” she wrote.

The Associated Press contributed to this report.