The Columbine school shooting in Colorado is a horrific example to have to learn from.
But law enforcement uses what happened there to better prepare for an active shooter anywhere.
Tonight we take you Inside the Academy...
As Amber Schatz shows you... recruits are no longer taught to wait for backup... but to take the bad guy out.
This training is intense.
Real shots are fired until the bad guy goes down and dispatch is called.
They're practicing how to call for backup after taking out an active shooter in a building.
Thankfully this is only a drill.
All of the recruits are learning how to respond if they were on patrol and alone.
"I'm a little bit nervous, but try to calm down a little bit because when you're nervous you can mess something up, focus... you rely back on your training and you'll do fine, so that's what I'm trying to do, right now trying to kind of calm myself down a little bit and let's hope everything goes well, and don't get shot, shoot the bad guy!" says Ves Marinov, Recruit.
The bad guy is actually a good guy.
Ben Kennelly is a state trooper from the Jamestown region.
He is getting pelted repeatedly by simulation, simulated ammunition.
"It hurts..." says Kennelly.
The pain helps him react differently each time a new recruit goes through.
"It's nice to be able to feel it so you know when you're being hit because it doesn't do us any good if I stand here and take 12 rounds point blank and stay standing, that's not realistic." says Ben Kennelly, Trooper in the Jamestown Region.
He is firing blanks, but providing a stressful scenario for each officer to respond to.
"The biggest thing for us is if mistakes are made, we want them to make them here, and as long as they learn from that, overall, we're just giving them options, putting them under stress." says Kennelly.
He's been in real standoffs while on patrol.
This part of his job is to better prepare future troopers to take on any challenge head on.
"It gives them the experience of okay, I've done this, I can work through it to win... Don't give, up, that's the best advice I can give." says Kennelly.
Reporting in Bismarck, I'm Amber Schatz.
Four of the recruits with previous law enforcement will be sworn in tomorrow then head out west to patrol.
Two more advanced level recruits will be moving on in the next two weeks.
The rest of the class will graduate in June.