The mass shooting at Virginia Tech, which killed 32 people three years ago Friday, touched off an intense debate over whether colleges should remain gun-free zones, or whether allowing students and faculty to carry concealed weapons might have resulted in fewer deaths. Though the debate continues, so far colleges have generally declined to move to allow concealed guns on campus – and most state legislatures have not forced them to do so.

Today 26 states prohibit conceal and carry on college campuses, and 23 states leave the decision to the schools, according to the nonpartisan Project America. In these 23 states, a large majority of colleges prohibit conceal and carry.

Only Utah has a 2004 law requiring publicly funded schools to permit students over 21 with conceal and carry licenses to carry guns on campus.

“After Virginia Tech, we faced a push by the gun lobby to expand conceal-and-carry rights at colleges,” says Andy Pelosi of the Campaign to Keep Guns Off Campus. “But we have been trying to raise awareness, and more and more people are joining our cause.”

This year at least 10 state legislatures are considering bills dealing with guns on campus, he says.

Gun rights proponents argue that colleges should allow students and faculty to carry concealed weapons as a deterrent and as a means of protection in situations such as the Virginia Tech shooting, in which a student with a history of mental illness went on an extended rampage against fellow students and faculty before shooting himself. Gun control advocates respond that allowing students to carry concealed weapons would create more violence, not less.

Since the Virginia Tech tragedy, measures to allow concealed carry on college campuses have stalled or been voted down in state legislatures 34 times, The Wall Street Journal reported in July 2009. No laws allowing conceal and carry on campuses have passed since then, says Mr. Pelosi.

Last year, Texas, Tennessee, and Louisiana each voted on measures similar to Utah's. The votes in Texas and Tennessee were close, but the bills failed. Louisiana voted the measure down 86 to 18.

“Texas was a huge win, but we knew they’d be back,” says Pelosi, referring to gun rights groups and their allies in the legislature.

Students who support broad gun rights are mobilizing. Last week, Students for Concealed Carry on Campus reported holding “Empty Holster Protest” events at dozens of college campuses. Participants wore empty holsters to show they are legal gun owners forbidden to carry concealed firearms at their schools.

“We call gun-free zones ‘disarmed victim zones,’ ” Steve Khemthong, a participant in the Empty Holster Protest and a student at Central Connecticut State University, told the New Britain Herald. Mr. Khemthong’s gun club hosted “NRA University,” a two-hour seminar discussing US gun laws and the work of the National Rifle Association. During the seminar, the NRA’s Seth Waugh encouraged various forms of pro-gun activism, such as communicating with state legislators and volunteering for a campaign, the Herald reported.

Despite legislative setbacks, gun rights advocates have achieved some success in the courts. On Thursday, a Colorado appellate court ruled in favor of Students for Concealed Carry on Campus, finding that the University of Colorado’s rule prohibiting conceal and carry violates the state’s 2003 Concealed Carry Act.

The university is considering appealing to the Colorado Supreme Court, spokesman Ken McConnellogue told the Associated Press. If the school does not appeal, gun-control proponents in the legislature are expected to try to rewrite the law in question – the Concealed Carry Act of 2003.