CLEVELAND, Ohio -- The growing distrust between Cleveland police and the communities they serve can be attributed in part to how quickly officers draw their weapons without trying to use words to calm tense situations, according to the U.S. Department of Justice investigation of the Cleveland Division of Police.

In addition to finding that police often fire their weapons recklessly, the report called out police for using deadly force or less lethal force as their first approach rather than a last resort, even in cases where a suspect is mentally disabled.

"We...discovered that officers do not effectively de-escalate situations, either because they do not know how, or because they do not have an adequate understanding of the importance of de-escalating encounters before resorting to force whenever possible," the report says.

These practices have become routine in a police culture that encourages using force as punishment - a pattern that's not only illegal but also puts a strain on police-citizen relations, according to the Justice Department.

The law allows police to use deadly force when their lives or the lives of others around them are in danger, but the Justice officials slammed Cleveland police for shooting at or using other means of physical coercion against people who were not a threat.

The recent case of a 12-year-old Cleveland by shot by police at a city park was not considered in the investigation. But many of the force related issues involved in the Justice Department review have been raised in the Tamir Rice shooting. Some have criticized officer Timothy Loehmann for shooting the boy within seconds of coming into contact with him and others questioned whether sufficient verbal commands were made.

The 20-month long Justice Department investigation found that in the rare instances when Cleveland officers verbally confront a suspect, they usually do so with their weapon drawn. That creates distrust between police and the community.

Departments that develop a reputation for being violent are likely to face tension within the communities they serve, according to Sam Walker, criminal justice professor at the University of Nebraska at Omaha who has done extensive research on police accountability.

"If officers are less quick to use weapons or other kind of force, there's going to be more opportunity to resolve the encounter reasonably without use of force, injury or chance of death," Walker said.

The tendency for officers to pull out their weapon right away is deeply ingrained in police culture, according to Walker.

Police who are insulted by a suspect often let their emotions get to them and they lash out in anger by resorting to force, Walker said. The Department of Justice found a troubling pattern of police losing their patience with people who were not cooperating or challenging their authority.

Veteran officer and former president of the Police Foundation Hubert Williams said the ability to talk a suspect down is the mark of a responsible officer.

"The best capability of an officer is to utilize communication as their primary weapon against somebody that might constitute a threat," said Williams.

In his 30 years on the force, Williams said the best officers he knew rarely drew their weapons.

Justice officials were also critical of the police department's tactics for dealing with mentally ill people. Here too, police are too quick to employ force without trying to verbally control the situation.

During an incident in 2013 when Cleveland police responded to a call for a mentally ill man threatening to blow up the government, officers handcuffed him and put a hood called a "spit sock" over his head because he was spitting at them. In the police car, the man began kicking at the windows.

The extent of a sergeant's attempts to defuse the situation was "ordering him to stop" before proceeding to pepper spray his face over the spit sock. The report calls the use of the spray an unnecessary punishment.

The investigation found the majority of officers on the force have no training in encountering people with mental illness. Police haven't offered any in-service mental health training since 2010, the report says. However, nearly 400 officers have received 40-hour Crisis Intervention Team training and certification through the Alcohol, Drug Addiction & Mental Health Services Board of Cuyahoga County, police said.

The Justice Department said even in instances when Cleveland police are within their legal rights to pull their weapon, it doesn't necessarily mean they should.

"While these tactical errors may not always result in constitutional violations, they place offenders, suspects and other members of the Cleveland community at risk," the report says.

Police are trained to follow a use-of-force continuum that starts with officer presence and progresses to verbal commands before using any kind of physical or deadly force, according to Mike Miller, former police officer and professor at South College in Florida who has done research on use of force.

Miller describes the continuum as a series of decisions an officer makes about the level of force they need to counter resistance from a suspect.

He said pulling a weapon when it's not necessary could put an officer and those around them in danger. A suspect can more easily disarm an officer when the gun is out of its holster, and this also heightens the risk for accidental firing.

This Justice report cited two examples of this in its report, including one incident in Cleveland in 2012 when an officer pulled over a man whose car was blocking traffic. The officer approached the man's car with his gun drawn, and told him to turn off his car. The man didn't obey, and the officer reached inside his car, accidentally shooting the man in the chest.

"If you could verbally de-escalate resistance, and the suspect does that, you should stop and reassess," he said. "Once you determine you don't need your weapon pulled, holster the weapon and move on."

Thomas Aveni, executive director at the Police Policy Studies Council, said verbal commands are key to police encounters, because that's when suspects make their decision of whether they'll cooperate with the officer.

"That's where a suspect has a great deal of influence on whether or not he's shot," Aveni said.