BOULDER, Colo. — During her 19 years teaching English at the University of Colorado Boulder, Karen Jacobs never gave much thought to whether one of her students was carrying a gun.

As the state’s flagship university, it had a longstanding firearms ban. So even in a place like Colorado, where gun rights are nearly as deeply cherished as John Elway and fresh snow, there was never a need for concern.

But ever since a State Supreme Court ruling in March forced the university to allow those with Colorado concealed weapon permits to carry their guns on campus, Ms. Jacobs and other faculty members have found themselves increasingly uneasy.

“This is a place where we depend on being able to speak our minds and offer sometimes controversial opinions in a free and open place,” she said. “The feeling among a percentage of faculty is that this will create a climate of fear and intimidation.”