A veteran journalist who witnessed the mass arrests during the G20 summit four years ago told a police disciplinary hearing Thursday that in his 32-year career he had never seen Toronto officers "kettle" peaceful protesters.

Steve Paikin, who hosts TVO's "The Agenda," testified in a hearing for Supt. David (Mark) Fenton, the most senior police officer charged in the mass arrests during the meeting of global leaders.

Paikin told the judge that before the night of June 26, 2010, he had never seen police in riot gear box in protesters who didn't appear to threaten public safety.

"I've never seen this much riot gear, never seen the kind of hemming in that officers did this time," he said.

In the past, he said, police only intervened when protesters became "overly aggressive."

"Those were not the conditions on the night in question," he said, noting the crowd gathered outside a downtown hotel was sitting and chanting the words "peaceful protest."

Fenton ordered officers to box in protesters in front of the hotel. More than 260 people were arrested and taken to a makeshift prisoner processing centre, which came under severe criticism for its deplorable conditions.

He has pleaded not guilty to a total of five charges of unlawful arrest and discreditable conduct arising out of two "kettling" incidents that occurred over the summit weekend, including the one that took place outside the hotel.

Prior to that incident, a small group of vandals smashed windows and set police cruisers alight elsewhere in the city's downtown.

Paikin followed protesters

Paikin said he had followed a spontaneous and organic protest down from Queen's Park and through the downtown core after hearing about the vandalism.

It had been raining on and off, he said, so the crowd had thinned out by the time they reached the hotel. People sat down.

Soon, a line of police officers carrying shields and batons arrived on one side of the group, then on the other, effectively containing the protest, he said.

At one point, Paikin said he felt something whiz by his ear and, not knowing whether it was a rubber bullet or something else, he took cover behind a pillar at the hotel. He could still see the protesters but had to peek out to see police, he said.

"At some point, I presume, an order was given that the area had to be cleared out," because the lines of officers began to move in, he said.

Police called out through a megaphone that anyone who didn't take off would be arrested, Paikin said, though other witnesses have testified they weren't given a chance to leave.

He acknowledged that people might have been afraid to cross the police lines. "It's reasonable to infer that if they wanted to get up and leave, they might not have felt safe," he said.

Shortly afterward, officers began to pick up protesters and put them in a court services vehicle, Paikin said.

That's when police politely asked him to leave or face arrest, despite his official G20 media accreditation, he said. After weighing his options, Paikin said he decided to leave so he could report what he had seen, and was escorted away from the area.

Fenton's defence lawyer argued Paikin had no way of knowing the protesters were in fact peaceful or what kind of intelligence police may have had.

The charges also stem from a second incident that occurred the next day when Fenton ordered police to keep scores of people standing for hours at a downtown intersection despite a severe thunderstorm that left them drenched.

Fenton's disciplinary hearing is expected to last for six weeks.