LANSING, MI -- Michigan Education Association President Steve Cook today formally endorsed legislation designed to close what he called a "dangerous loophole" in Michigan law allowing concealed pistol permit holders to openly-carry guns in schools.

Cook joined bill sponsor and Democratic state Rep. Andy Schor of Lansing at the Michigan Capitol, making the case for HB 4104 on the three-month anniversary of a deadly shooting at Sandy Hook Elementary School in Connecticut.

"Schools are supposed to be safe havens so Michigan's children can focus on learning and exploring -- not worrying about whether someone with a gun will walk through the front door, weather that gun is on their hip or in their jacket," Cook said, suggesting Democrats and Republicans should be willing to support the "common-sense" bill.

Michigan law prohibits permit holder from carrying concealed weapons into schools and other "gun-free zones," but a statutory loophole does not prevent permit holders from openly-carrying in those areas.

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Last year, open-carry advocate Nicholas Looman walked into Aberdeen Middle School in Grand Rapids with a holstered pistol on his hip. A staff member stopped and questioned him, and the district temporarily banned him from school property. The Kent County prosecutor said that while he showed "extremely poor judgement," Looman had not violated any state laws.

Citing that example, Schor said open-carry in schools could cause students and staff to panic, even if that individual is a licensed permit holder. "As a gun owner, I recognize the importance of the Second Amendment, but in this case, allowing openly-armed civilians to roam the halls of our schools is a recipe for disaster," he said.

In addition to closing the loophole, Schor's legislation also would add libraries to the state's list of gun-free zones. That portion of the bill is a direct response to a court of appeals ruling that lifted an injunction previously granted to the Capitol Area District Library, which had stopped members of Michigan Open Carry Inc. from carrying pistols into Lansing-area branches.

MOC President Phillip Hofmeister opposes both elements of Schor's bill. Open-carry is entirely lawful, he said today, and should not be restricted. "I think people need to have a way to protect themselves wherever they go, and because of current pistol-free zones, it's the only way people can protect themselves in some places."

House Speaker Jase Bolger has not taken a position on Schor's legislation, which was introduced in January. "The bill will need to move through the committee process where it can be properly vetted to determine if it's the right policy to address the growing concerns over both school safety and the Second Amendment rights of Michigan's gun owners," said spokesman Ari Adler.

If the bill does get a committee hearing, Hoffmeister said his group would lobby strongly against it. "That bill was dead upon arrival from our point of view," he said. "A similar bill was introduced last year, and that went nowhere."

Separately, Republican state Sen. Mike Green of Mayville has reintroduced legislation seeking to eliminate Michigan gun-free zones. While the legislature approved a version of the bill last year that Gov. Rick Snyder ultimately vetoed, the legislation appears to have stalled upon re-introduction.

"We've had a robust conversation across the nation about gun violence and school safety, and that's a conversation that needs to happen and should continue," Cook said at today's press conference. "…We know that something must be done to protect our children from these acts of violence. But as both an educator and gun owner, I say this: Having more weapons in Michigan schools is not the answer."

Editor's note: This post was updated to specify that only concealed permit holders currently are allowed to open-carry in gun-free zones due to a statutory loophole.

Jonathan Oosting is a Capitol reporter for MLive Media Group. Email him, find him on Google+ or follow him on Twitter.