The letter was presented to a three-member faculty committee considering a grievance filed by associate professor Alain Bourget, who in spring 2014 dropped the long-used textbook co-written by the department's chairman and vice chairman. Bourget opted instead to use new -- and cheaper -- course materials he thought were more relevant.
Bourget received a letter of reprimand for failing to use the assigned book and not following department procedures. He has argued that there was no clear policy preventing him from using a different book.
The case has sparked a national debate over academic freedom and the circumstances under which professors should assign their own books to students.
After the hearing, Bourget said he was disappointed that his case has caused so much dissension.
"A lot of people are taking it personally and feel like I'm attacking the university," he said.
The hearing panel has 14 days to consider its findings and make a recommendation to university President Mildred Garcia on whether to revoke the reprimand.
The faculty letter presented to the hearing panel said that many other departments do not require a single textbook for all course sections and other have an explicit process for textbook selection, "but the vast, vast majority of departments resolve these questions amicably and according to well-documented processes."
"There is a time and place for a censure action," the letter said. "That time is not when in good faith an expert in the field seeks to improve the quality of the curricula and the policy is unclear."
Campus officials would not directly comment on the hearing.
But in an email, David Bowman, interim dean of the College of Natural Sciences and Mathematics, defended the math department's procedures.
"In the case of courses with multiple class sections, textbook selection may be shared across multiple instructors," said Bowman, who wrote the letter of reprimand. "Departments may elect to use a single textbook in such instances, particularly in courses where the subject matter is closely tied to the curriculum in subsequent coursework."
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