Edmonton's police chief is being ordered to re-investigate a botched high-risk takedown that terrorized two co-workers leaving work.

The Law Enforcement Review Board called it unreasonable that Acting Chief David Korol dismissed the complaints of the victims.

"As this appeal involves both use of force on innocent citizens and an unacceptably inadequate investigation, it is unreasonable for the Chief to have reached the decision he did," the board concluded.

'That the incident was an 'unfortunate error' does not excuse the fact it happened and could happen again'—Law Enforcement Review Board

The police gang and drug unit was tracking a suspected drug trafficker driving a Lexus when it lost sight of him at Riverbend Square in southwest Edmonton on April 28, 2009.

Shortly after officers saw what they thought was that car involved in a drug deal in the parking lot.

Police vehicles boxed in the car as officers spilled out pointing rifles and smashing windows before throwing the driver to the ground and handcuffing him. They also handcuffed a second person in a separate car.

The "suspect" turned out to be an employee of a nearby pharmacy driving a Mazda who was chatting with a co-worker.

Realizing their mistake, officers assured Roy Persaud and Salimeh Jetha police would pay for damages to their cars and offered to buy them a cup of coffee.

Persaud and Jetha complained to the chief.

Korol dismissed the complaint, saying the officers' use of force was justified because they reasonably assumed they had the right man.

He concluded the incident was nothing more than an unfortunate error.

The Law Enforcement Review Board disagreed and ordered new police chief — Rod Knecht — to look at why police made this mistake and how to make sure it doesn't happen again.

"That the incident was an 'unfortunate error' does not excuse the fact it happened and could happen again," the board said in its written decision.

"Before unleashing the full force of a police Tactical Team, it must be ascertained that the object of the takedown is in fact the targeted suspects and not unsuspecting innocent citizens going about their business."

Erica Norheim, the lawyer who represents Persaud and Jetha, said the police initially tried to ignore the incident. "I don't think that it was dragging their feet so much as wanting to sweep it under the rug."

But with the ruling, "I have confidence that they will do a full investigation to find out exactly what went wrong in this case."