One of the questions in a recent legal ethics exam, looking at the cab rank rule - that lawyers have to take whoever requests their services - had "strong similarities to the recent Christchurch tragedy".
The law faculty apologised the following day.
A student told The New Zealand Herald one of those sitting the exam had a cousin killed in the attacks.
OUSA president James Heath said it was "an insensitive and unfortunate situation, particularly when students were not expecting to see this".
However, he considered dean of law Prof Jessica Palmer and the law faculty had handled the situation well.
It was reported the question led some students to break down and cry during the exam last week.
The Society of Otago University Law Students (Souls) declined to comment, and the Otago Muslim Association also declined to comment.
Prof Palmer said in a statement the faculty had moved quickly to apologise and explain the situation, and had offered help to students who considered their performance had been impaired.
The day after the exam, she sent an email to students:
"I have been made aware of a question included in the legal ethics exam yesterday which concerned a hypothetical scenario that had strong similarities to the recent Christchurch tragedy.
"While we endeavour to include real-world scenarios in our courses and examinations, given these recent events Question 41 was clearly inappropriate.
"I acknowledge that some of you will have been upset by the question, and that this may have also led to added anxiety during the examination.
"I am sorry that we have let you down on this occasion. I am particularly sorry to those of you for whom this question brought back painful memories."
The examiner, who set the question, also apologised.
"My intent was to come up with a situation where the cab rank rule would impose a truly horrific burden on a lawyer, leading to a discussion about good cause and whether the rule should be retained," the examiner said.
"I should have realised that the scenario I presented was likely to cause distress, and I am deeply sorry."