CLEVELAND, Ohio -- Cleveland police will stop hitting people on the head with their guns and document any time they unholster them, according to a consent decree between the U.S. Justice Department and Cleveland police released today.

The Justice Department found in a 21-month investigation that began in 2013 that Cleveland police routinely bash people on the head with their guns, sometimes accidentally firing them, according to a 58-page report released in December.

The consent decree released Tuesday between the U.S. Department of Justice and the city of Cleveland is the result of five months of negotiations, as well as dozens of meetings with community groups, church leaders and advocates. Once approved by a federal judge, the city is legally bound to enact the reforms included in the 105-page document, meant to protect citizens' Constitutional rights.

"[Cleveland Division of Police's] policy will expressly provide that using a firearm as an impact weapon is never an authorized tactic," the consent decree says. "Officers will be trained that use of a firearm as an impact weapon could result in death to suspects, bystanders and themselves."

The agreement prohibits officers from displaying their firearms unless they believe lethal force is necessary. It also requires Cleveland police train officers to de-escalate situations, including by using verbal persuasion and warnings, instead of approaching suspects with guns drawn.

The mandates are standard police tactics, said Sam Walker, a retired criminology professor at the University of Nebraska at Omaha and a Cleveland Heights native.

"Many of the things are the long-standing policies in these good department. Like hitting people with their guns, like a baton," Walker said. "The good departments banned that decades ago."

The December report revealed officers often provoke situations by drawing their weapons at inappropriate times. The approach increases the possibility of violence and leaves officers with only one free hand.

"It is also unclear why CDP appears to be categorizing hitting someone with a gun as a conventional response when force is needed," the December report said. "This is uniformly understood to be a dangerous practice that should never be permitted except in very unusual and exigent circumstances in which the use of deadly force is authorized; yet, it was a practice we saw CDP officers engaging in too frequently."

The Justice Department made an example of a 2012 encounter when an off-duty officer drew his gun after a suspect asked him to show identification. Wrestling ensued, and the off-duty officer struck the man in the head, causing the gun to fire.

In another incident from 2011, a police officer working as a convenience store security detail used his gun to hit an unarmed shoplifter over the head.

"Again, this use of deadly force against a man who was not armed, had committed a minor offense, and who presented only a minimal threat to the officer was unreasonable and dangerous," the Justice Department said in its December report.