SEATTLE -The Washington State Patrol has been using cameras in patrol cars for years.
State trooper Brian Dixon says he loves his camera. It's like having a witness ride along with him.
"It's a safety net of reducing my liability," Dixon said. "Basically, it's indisputable. It shows exactly what happened."
Videotape provides accountability for the public and for police. But car cameras only capture what's happening directly in front of the vehicle.
What if the camera was so small it could be worn by the police officer?
Three Seattle police officers who worked in SWAT and taser units left the department to develop and market wearable cameras they call VIEVU, or Life View. A wireless, mini camera made by VIEVU weighs three ounces and is about the size of a pager. It can record up to four hours at a time.
"You can wear it on your lapel. You can wear it on your shirt. You can wear it on your belt," said Steve Ward, president of VIEVU.
From its headquarters on Queen Anne Hill in Seattle, VIEVU is shipping thousands of cameras to police agencies around the world. The Seattle Police Department and several other local police departments are quietly testing them here, but won't say if they plan to make them part of their arsenal.
The small camera was developed primarily for patrol officers handling potentially volatile situations.
"But it's also ideal for motorcycle units, bicycle units, foot patrol, horse mounted units, even SWAT," Ward said.
Ward says the camera protects officers from being falsely accused, but can also help weed out bad cops.
"You will find times where the officer did cross the line, and what this does is enable the police department to have the evidence they need to actually take care of the problem," Ward said.
There's no rewind or erase button. The video gets downloaded into a computer where it can't be altered.
Still, the American Civil Liberties Union says personal police cameras raise some concerns.
"You don't want it to end up recording everything the officer sees at every moment going about their business because when you do that you end up with a lot of surveillance footage of innocent activities," said Christina Drummond, Technology and Liberty Project Director for the ACLU of Washington.
By law, police are required to tell citizens they're being taped and their voice recorded.
And they acknowledge they will need to establish careful guidelines for using the wearable cameras because of the kind of issues raised by the ACLU.