The Illinois Council of Police, in a letter to Mayor Rahm Emanuel, said the current policy, which prohibits all aviation police officers from carrying a gun, puts them and the public in danger.
"At a time when threats to our airports and other vulnerable entities within the United States are at its greatest, we renew our request that these fine officers be given authority to carry a firearm as part of their duty gear as is the norm at all other major airports within the United States for their safety and that of the public at large," said the letter from union President Norm Frese.
The letter follows a CNN investigation
that revealed aviation police are not armed and are told to "run and hide" in the event of an active shooter or other threat at both O'Hare and Midway. Many of those officers are either military veterans or work in suburban police departments.
A long-standing policy prohibits aviation police officers from carrying a gun even though they are certified law enforcement officers. About 300 of them work along with armed officers from the Chicago Police Department, which is the primary law enforcement agency at O'Hare and Midway.
"We submit to you that the current approach to law enforcement by the aviation police, specifically concerning responses to terrorist or other threats, is seriously flawed in that they are handicapped in their duties because of a lack of a firearm," the Illinois Council of Police letter said.
It said the current policy "that seeks to avoid an aviation officer from becoming part of the response makes it more dangerous for themselves and the public at one of the largest airports in the United States."
Richard Bruno, vice president of the Illinois Council of Police, which represents the 28 aviation police sergeants, said all that would need to be done is a policy change to allow officers and supervisors to carry a gun at the airports.
"It is a danger to the public," Bruno told CNN. "First of all, you are in a uniform, and you have the authority of a policeman. Guess what people think -- you are a policeman."
The union that represents the aviation police officers at the two airports also has demanded that they be allowed to carry a gun.
Previously, the deputy communications director of the Chicago Aviation Department told CNN that the department thinks "the strategy in place is working."
In a statement to CNN, Owen Kilmer wrote that with "the current security structure in place, violent crime incidents at O'Hare and Midway airports are extremely low -- ensuring that the millions of passengers who fly through Chicago each year feel secure at the airports."
Matt Brandon, the secretary/treasurer of Local 73 of the Service Employees International Union (SEIU), told CNN that no commitment was made to change the no-guns policy when he met last week with Ginger Evans, the Chicago aviation department's commissioner.
Brandon, in an e-mail sent Tuesday to Evans, again criticized the department's "run and hide" directive given to aviation police officers for handling active shooters.
"I also told you that because of the training that these Law Enforcement Officers receive that it would be fatal for any APO (aviation police officer) in the vicinity of an 'active shooter' because they would be the first ones targeted because they are a uniformed presence," Brandon's e-mail said.
"You then explained to me that you rely on statistical data that suggests that because there has been no attack on O'Hare and Midway Airports that the likelihood of such an event occurring was low. I referenced the fact that no airplanes had been hijacked and purposely flown into skyscrapers before 9/11, but once was enough to cost thousands of innocent people their lives. You took exception to that and explained your background of having worked with federal authorities immediately after that horrible incident but I've always been taught to be proactive, not reactive. That's what saves lives Commissioner."
Asked for a comment about the meeting, an aviation department spokesman told CNN in an e-mail, "We don't provide details on private conversations."
Repeated requests from CNN for a comment from Emanuel have gone unanswered.