Why do cops use deadly force?

TRI-CITIES, Wash. -- After three officer-involved shootings in a month, people still ask why police need to use deadly force so quickly.

And then there's the shooting of an unarmed teenager outside St. Louis.

Officers reviewed why they have high-powered rifles and armored vehicles and why they're ready to use them at a moment's notice.

Richland Captain Mike Cobb watches a YouTube video of a shootout in North Hollywood back in 1997. Back then, armed men with machine guns walked the streets at will, firing their weapons. Police could only respond with pistols.

It's a historic example of why police now have to take drastic measures.

"In the 1980s, where we would have to use two or three magazines of handgun ammunition, now we can use one round of riffle ammunition," says Richland Police Captain Cobb.

He says he receives dozens of complaints every month from members of the community asking why officers need military-grade vehicles and large caliber rifles.

"Tri-Cities isn't that big. I don't know that we have anybody around here, crime-wise, that has anything like that. I don't think I've ever seen anything like that," says Tri-Cities resident Marie Bleazard.

She says she's glad the police keep the community safe, but wonders how far police will have to go to outmatch criminals.

Pasco's recent officer-involved shootings tell two stories.
In the first one in west Pasco, police used a military-style transport to rescue a man pinned down by gun fire from a suspect.

"We would have had human beings killed, had that armored vehicle not been available," Captain Cobb says.

In the second, officers shot a man who had a knife. Police say this weapon is still deadly and he wouldn't put it down.

"This is not a sporting activity. And so it isn't a question of having fairness. It's a question of stopping a life-threatening event immediately and we use that with firearms," the Captain continued.

Police say their hope is that members of the community will realize that their main goal is to keep everyone safe.

Police say most of the SWAT tactics aren't derived from the military rather, the military has adapted many of their tactics from local law-enforcement.

Investigations into all three officer involved shootings are still underway. They will determine if the use of deadly force was justified.