Nationwide, use of force by police has taken center stage. Officers say the decision to use force is one that's complex, and many don't realize just how quickly the decision has to be made.

Studies show less than one tenth of one percent of police calls end in officers having to use force. But recently, high-profile cases across the nation have put departments' policies in the spotlight.

The Pennsylvania State Police's Use of Force Unit has focused on training officers in this regard for several years.

"We focus on developing curriculum and developing training specifically in the area of police use of force and it's one of the only units of its kind in the country," said use of force specialist, Corporal Barton Lemansky.

On Wednesday, News 13 got a behind-the-scenes look at how cadets are taught to handle situations which could turn violent.

“A significant amount of stress is applied to the cadets when they’re here and that's for a reason. That’s so they can train themselves mentally and physically to function in that environment," said Corporal Lemansky.

They go through 1,100 hours of training, learning the laws they must follow in using reasonable force. In Pennsylvania, an officer is justified in using deadly force when they believe it is necessary to prevent death or serious harm to themselves or others, or if the subject commits a felony and is attempting to escape with a deadly weapon.

“It's easy to assume police officers have more time than they actually do to make these very critical decisions," said Corporal Lemansky. "It normally comes down to not seconds but less than one second in order to make these decisions in that environment while also under the influence of some degree of 'fight or flight' physiology which complicates that and shrinks the time even more," said Corporal Lemansky.

That's what police want the community to understand. Many times people form an opinion over whether an officer's actions were right or wrong using just a short video posted online.

“It's easy to assume a video clip tells you the whole story but it really is only a small piece of the story," said Corporal Lemansky.

But when determining whether use of force is justified, investigators actually look at many different factors and will even break video down frame by frame.

“That takes time, it's not done overnight. It takes a significant amount of time to really go into an incident and look at it to that level," said Sergeant Tim Fetzer, supervisor of the PSP Use of Force unit.

Police say the most important thing is for both sides to cooperate and respect each other, in order to keep incidents safe and peaceful.

"We want to treat you with the respect that if we put ourselves in your shoes that we would wish to be treated with and the same thing, we should garner that same respect from community members," said Sergeant Fetzer.