Harvard University’s reputation was threatened last week, when dozens of students were suspected of cheating on a take-home exam.

About half of the roughly 250 students in the undergraduate “Introduction to Congress,” which is taught by Assistant professor Matthew Platt, are being investigated for plagiarizing answers or collaborating inappropriately on the exam.

“These allegations, if proven, represent totally unacceptable behavior that betrays the trust upon which intellectual inquiry at Harvard depends,” Harvard President Drew Faust said.

Some students anonymously admitted to The Boston Globe they shared ideas and source material during the time they were given to finish the exam, but said the rules for the exam had been too unclear for them to realize they were cheating.

The instructions on the final exam said, “The exam is completely open book, open note, open internet, etc. However, in all other regards, this should fall under similar guidelines that apply to in-class exams. More specifically, students may not discuss the exam with others—this includes resident tutors, writing centers, etc.”

San Diego State School of Theatre, Television and Film Professor Greg Durbin, said the instructions for the take-home exam were not clarified.

“The professor for the take-home exam should have been more specific and more fulsome in the exam protocol,” Durbin said. “Also, I have to say apart from all that, conceptually I think he set himself up for a fall. That’s a flawed exam because it’s just so vulnerable to what happened even if it said students were not allowed to discuss the exam with others.”

Each of the students suspected of cheating was called before Howard’s Administrative Board and, if proven guilty, face punishments ranging from warning for a first defense to forced withdrawal from Harvard for a year.