My heart was pounding, my hand was hovering over my holster, and the guy in front of me was waving a handgun. Do I shoot him?

With all the controversy across the country over police shootings and use of force, D.C.'s police chief thought this might be a good time to run reporters through some very realistic scenarios, the kinds of things his officers might encounter on the street.

With just a half hour of training, I was at the DC Police Tactical Training Center with a simulated handgun, fake pepper spray, and an actor in the middle of the street cutting himself with a knife.

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I did the right thing by calling for back up who is specially trained to deal with the mentally ill, but then I got way too focused on the suspect. I forgot to tell my back up what he could do to help -- or keep an eye on the safety of the citizens around me.

He ignored me, so I hit him with non-lethal pepper spray -- which the instructor said was OK. Pulling my handgun when the pepper spray failed to work and the suspect was still waving a knife might have been smart -- holding both spray and gun at the same time was not.

But it worked out. I didn't shoot anyone, and neither me nor any bystanders got hurt.

The first session went much worse. Confronted by a man on a screen coming out of a trailer with a gun, I failed to draw my weapon or take cover. And I ended up dead.

“Last time I checked, we hire human beings, and human beings make mistakes,” said Chief Peter Newsham of the Metropolitan Police Department. “We're doing everything we can to make sure when our officers do have to use force, under those rare circumstances, that they do it in an appropriate way. And that's what this training is all about.”

The chief admits D.C. police once had a horrible reputation on use of force. But he says it's improved dramatically, in part because of training. The sanctity of all human lives is now written into the department's mission statement.