A Police Services Act disciplinary hearing officer found Const. Ryan Simpson acted reasonably and legally in stopping, handcuffing, searching and placing Nicholas Wright in the back of a cruiser.
The ruling released Friday says Wright matched the description of people who had broken windows and set fires during protests the previous day.
It also notes that Wright was carrying a metal container in his backpack, and calls the use of handcuffs reasonable until the backpack was searched.
The decision says Wright, who was released after about 19 minutes, was detained but not placed under arrest while the backpack was searched.
Wright says the decision is one more example of the failure to hold politicians and police responsible for what he terms "widespread unconstitutional mass arrests" carried out during the G20 summit.
"The finding that the offending officer did not in fact carry out an arrest defies common sense," he said in a statement.
"It is my view that the law has not been properly applied and I intend to seek to appeal this decision," Wright said.
"The officer in question admitted on cross examination that he arrested three others earlier the same day for wearing backpacks and neck scarves and that two superiors officers directed him to arrest all those dressed in a similar manner," Wright noted.
Wright's detention occurred on June 27, 2010 — a day after mayhem erupted in downtown Toronto when vandals mixed up with protesters went on a rampage.
Simpson maintained he stopped Wright for cycling fast between lanes of traffic. He said he then noted the rider had a neck scarf and swim goggles around his neck, was wearing a backpack, and a large group of cyclists was nearby.