As a citizen, when do you step in to stop a crime in progress? It's a question police are addressing after a wave of recent incidents in which witnesses confronted suspected criminals caught in the act. 

For Derek Homme of Palmer, a quick drive to satisfy a midnight ice cream craving put him behind a swerving truck and trailer that seemed like an accident waiting to happen. 

In compliance with REDDI protocol-- Report Every Dangerous Driver Immediately-- Homme called 911. 

"There was no troopers in the area, and they actually told me to discontinue at first, but the driving was just so egregious and such a public safety concern, I had to keep following him," said Homme. 

Homme followed the driver into a gas station, where the trailer hit the gas pumps, then confronted the man behind the wheel.

The seemingly impaired driver was compliant, at first, but then tried to drive away, according to Homme, who says he then opened the man's car door, jumped onto the man's lap and elbowed him a few times, then eventually pulled the emergency brake, took the keys from the ignition, and put the man on the ground where he searched him for weapons. 

Homme says he and other bystanders waited for troopers to arrive, and the driver was eventually arrested. 

"I couldn't in good faith just let him go and, "Oh, I hope I don't read about a fatality later," because that would be my fault, to an extent, if I didn't do anything about it," said Homme. 

He isn't alone in choosing to act. 

A class of carpentry students nabbed a would-be car thief last week, detaining him until police could get there. And an Anchorage store owner confronted the pair that tried to steal a $6,500 leather and fur coat, chasing them down and taking it back. 

"We don't want to encourage or discourage anyone from exercising their ability to effect a lawful arrest," said Anchorage Police Captain Michael Kerle. 

Kerle says citizens have the ability to make a citizen's arrest if they witness a crime, but choosing to do so requires knowing for sure that a crime is happening and using only reasonable force to stop it-- decisions that often have to be made quickly-- and which carry risk and liability.  

"The best thing to do is call the police-- we're trained," said Kerle. 

Kerle says they prefer citizens focus on being a good witness, and stay out of harm's way. The best way to do that, he says, is to call 911 and report the crime in progress, then pull out your phone and take pictures and video of what you see from a safe distance. 

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