An airline passenger says his pants were pulled down and his penis exposed during an "aggressive" pat-down at the Halifax airport.

Jerell Smith says his own investigation into how his complaint was handled "shocked" him as it revealed a gap in security at the section of the Halifax Stanfield International Airport controlled by the Canadian Air Transport Security Authority (CATSA).

Smith headed to the airport to start a vacation down south in October 2015. He went through screening, but was taken aside for secondary screening. Given a choice between a pat-down and a trip through the scan machine, he picked the pat-down.

The CATSA security officer started the physical search.

"That's when I knew he was upset, because it wasn't a search. He was patting me hard enough on my back that my body actually moved. I'm a big guy — I'm just over six foot, 270 pounds. To move me takes a little bit of force," says Smith, who works in law enforcement.

Officer pulled pants down

The officer lifted his shirt and the waistband of his jogging pants.

"This is all fine. I felt uncomfortable because of the force, but I let it go," says Smith.

He says he felt his pants slipping and asked the officer to take care.

"He said, 'This is our procedure. This is what you wanted, so this is what's going to happen,'" Smith told CBC News on Friday.

"He kept going, kept clasping, to the point where my pants pulled down — one side of my pants, the right side down to my knee. I did a squat to catch them because my underwear and my penis were exposed."

'This is the technique'

He said an older lady nearby seemed to have seen the whole thing and looked shocked.

Smith says he stepped back, pulled his pants up and spoke to the agent.

"He said, 'This is the technique, and this is what needs to be done before you can go through,'" said Smith.

CATSA's website says physical searches must always be done "in the most professional and respectful manner possible." Searches are "usually performed over clothing, though the screening officer may need to move, shift or slightly lift clothing."

Security camera 'watching a wall'

Smith complained to two supervisors at the site, but says he was told the fault lay in his clothing.

After his vacation, he talked to CATSA to file a complaint. He says CATSA told him they'd reviewed the security tape and found nothing to substantiate his claim.

CATSA agreed to show him the footage, which had four or five angles of the screening area. He saw only one glimpse of himself as he stepped back from the officer to pull up his pants.

"I was shocked. My search — that whole area — there was no actual camera on," he says. "I couldn't believe it. At that point I was a little upset. I said, 'The reason you can't substantiate it is because there's no angle to see it.'

CATSA controls security area

"I said, 'This camera angle is ridiculous. It's watching a wall.' That's when I lost trust in the process."

CATSA controls that area, as well as the cameras in it, a Halifax airport spokeswoman said.

I'm concerned that I can't see myself being searched and that basically no one can - Jerell Smith, passenger who was searched

"I'm concerned that I can't see myself being searched and that basically no one can," Smith said.

"If someone were sexually assaulted, for instance if a female went through and said, 'You know what? This person groped me or this person touched me inappropriately,' they would be in my shoes where it's not seen."

A CATSA spokesman told CBC News it had investigated Smith's complaint.

"After reviewing the footage and interviewing the screening personnel and also talking to the passenger on the phone, the investigation concluded that the allegations that were made — especially about the physical search — were not substantiated," Mathieu Larocque said Friday.

Larocque would not say when the staff member was interviewed. He also repeatedly refused to say if the video actually showed the full bodies of both men, and declined to say if there was a blank spot in their camera coverage of the screening area.

CBC reporter Alison Crawford obtained a copy of CATSA's initial report in an earlier investigation.

CATSA's report of the initial complaint. "PAX" is passenger, "SO" is security officer, "PBS" is pre-board screening and "PSOP" is physical search of person. (CBC)

CATSA staff told Smith there was no other footage — which made him wonder how they had concluded his complaint was unsubstantiated. They also told him they hadn't spoken to the officer or anyone else on duty that day.

Smith says his home security system has better cameras than those at the security area.

"It's inadequate for what airport security should be in 2016," he said.

CATSA dismissed complaints

Smith felt "this whole process wasn't necessarily to get to the bottom of what happened. It was to get the complaint ended."

CATSA later wrote to tell Smith none of his complaints had been substantiated and barring further action, the file would be closed within 30 days. That's when Smith gave up. He told plenty of people about the search and one of them saw the CBC story last week.

The complainants in that story were not named, but Smith was the one subjected to the "accidental strip search." That's when he called CBC to share his story.

"I was happy to see it. It told me that maybe I should step up and look into it further," said Smith.