Khalil’s arrest could have a chilling effect on on- and off-campus protests involving people who aren’t citizens, said Columbia University immigration law professor Elora Mukherjee. Already, she said, it had provoked panic and fear among immigrant students on campus.

A group of federal, state, and local officials in Michigan is calling for the release of Mahmoud Khalil, a Columbia University activist who was arrested by federal agents after leading pro-Palestinian protests last year.