He said college public safety officials wanted to be able to identify people who were in college buildings. He also said the development of the policy had no connection to the arrest of a 2008 graduate of the school, Tarek Mehanna, last year on charges of plotting terrorist attacks.

"Unequivocally, it has nothing to do with that case," he said.

Ratty said the college had found two people who would be affected by the ban, officials had met with them, and they had agreed to comply with it.

"We have faith that [the policy] is appropriate," he said.

But Hooper said he had not heard of such a policy adopted at any other American school. And he argued that since the policy includes a medical exemption, it should include a religious exemption.

"People should have the right to practice their faith as they see fit, not as others see fit," he said.

Sarah Wunsch, staff attorney at the ACLU of Massachusetts, said the policy was "puzzling and possibly illegal."

Founded in 1823, the private college has prepared more men and women for professional careers in pharmacy than any other academic institution in the world, according to the school's website. It has 4,300 students who pursue 30 programs in pharmacy and a variety of other health care-related fields.