Sitting at an L-shaped desk in the large office shared by the Yukon's two forensic identification officers, RCMP Cpl. Jim Giczi is remarkably modest about his role in capturing Canada's most recent – and highest-ranking – serial killer.

"Yeah, my dad read about it and called to congratulate me last week,” Giczi says.

He sidesteps further praise for the fact he is the sole creator of the tire-track database which led investigators to suspect then-col. Russell Williams for the disappearance of 27-year-old Ontario woman Jessica Lloyd in August.

Williams ultimately admitted to two murders, two sexual assaults and more than 80 break-ins last month. He did so after police became suspicious of him based on the fact his unique tire treads matched imprints found in a field beside his last victim's home.

Meaning Giczi didn't call up every single person he knew to let them know he had played a crucial role in the capture of an affirmed psycho-sexual predator who otherwise may not have been caught?

"I'm just doing my job,” Giczi replies.

His job is the real-life version of CSI: Yukon, he says with a rare laugh. "Except it's not like it is on TV.”

The difference, says Giczi, is the speed at which investigators can get results from the various tests they run on evidence taken from a crime scene, and the kind of detail they can glean from that evidence.

"We look at surveillance video here,” he says, pointing at a state-of-the-art computer system, compatible with any digital or analog recordings that may come across Giczi's desk. "But we can't zoom in on a surface and see the suspect's face in the reflection like they do in the movies.”

Same goes for the compact crime lab adjoining the office Giczi shares with Sgt. Doug Spencer.

Here, the investigators lift fingerprints, develop photos, examine boot marks and work to get the most information they can out of the clues left behind in every case. But it all takes patience and footwork, he says, not just the touch of a button as it does in TV land.

Giczi has testified in most of the Yukon's high-profile cases since he arrived in the territory in 2002, and has been accepted as an expert in fingerprints, footprints, and tire impressions.

Distinctive markings, it seems, are his specialty. He once assisted an investigation into the illegal cutting of trees from the Ibex Valley. He had to give himself a crash course in what makes each tree unique so he could link the logs that fell from the back of a truck to the stumps left behind.

The database which has put (a very modest) Giczi in the limelight came to life following a break-and-enter in Whitehorse.

The 47-year-old corporal had photographed a tire imprint at the scene, but when he returned to the office to compare it with the database then in use, he found the collection of often blurry photos of varying size and quality, taken at different angles, was of little use to him.

Giving up on the available database, he headed to Integra Tire to see if he could identify the track simply by comparing the imprint to the tires Integra had in stock.

An auxiliary constable who works at the tire shop helped him out and they soon found a make and model match.

Giczi returned to the detachment and passed on the information to the investigators, but the idea stuck – and grew.

"It wasn't so much of a eureka moment as realizing there had to be a different way of doing things,” Giczi says.

Creating a new and more usable database turned out to be fairly straightforward.

Instead of going around and photographing every tire in every shop, Giczi simply scanned photos taken from catalogues and pamphlets.

The pictures were clear, and almost always taken from the same angle. The markings were well-lit and easy to distinguish, and once he had a system down, it only took him about five minutes to enter the photo, get it to the right size and angle, and enter the cataloguing criteria.

At first, he imagined a purely local database, "because let's face it, we're a thousand miles from anywhere, so we have a pretty captive audience,” Giczi says, "but it just kept growing and growing.”

Other officers began sending the corporal tire pamphlets from their jurisdictions and now every time Giczi goes to a conference or takes a trip, he picks up more. Now he's started getting information from the United States as well.

"There was an article about it in a Canadian ident journal, and through that I've even been connected with U.S. pamphlets,” he says.

Three narrow file boxes stuffed with catalogues sit over his desk, some waiting to be entered.

From an original database of about 265 tires when he first started, Giczi has now entered more than 1,100 treads into his computer.

"I do it whenever I have time, off the side of my desk,” he says. "It hasn't cost anything to do.”

Now this Yukon-born database has replaced the previous, poor-resolution, catalogue Giczi used back in 2007. (It is a commercially available system which the RCMP licensed from a private company.)

Police forces all across the country use it and the corporal heard recently that the FBI has put it into their investigative arsenal as well.

At the same time as Giczi was first developing his idea, in a quiet military town in Ontario, ex-col. Rus Williams, a shining star in the country's air force, was committing his first break-ins.

At first his crimes, though bizarre and frightening, were relatively benign.

He would break into women's homes and steal their clothes, underwear and personal photographs, sometimes leaving behind messages typed on their computer screens.

What police didn't know at the time is that he was also photographing himself in their homes, wearing the clothes and masturbating.

He left behind DNA in many of the break-ins, but that didn't help police, as Williams was not on any criminal databases.

On the contrary, he was an upstanding citizen, the pilot entrusted to fly the Queen's plane during her last visit to Canada, the commander of his base.

Certainly not a man the police would ever suspect of the bizarre break-ins, then a pair of frightening sex assaults where the victims were bound and photographed by their assailant.

Then the violent murder of Marie-France Comeau, a 37-year-old corporal who worked on Williams' base. Then the disappearance of Jessica Lloyd.

Police knew it had to be someone in Williams' neighbourhood; in fact, they searched his next-door neighbour's house and brought the man in for questioning, but they never suspected Williams.

In the days following Lloyd's disappearance, another neighbour contacted police to tell them he had seen an SUV parked in the field beside Lloyd's house the night she went missing.

Investigators, aided by a sprinkling of snow, were able to pull a clear tire print from the area. They compared it to Giczi's database and had the tire make and model they were looking for.

Roadblocks were set up in the area and that night, Williams drove his SUV past a young Belleville, Ont. police officer who noted a perfect match between the type of tire that left tracks outside Lloyd's house and the tires on Williams' vehicle.

The colonel was put under surveillance, and within days, he would lead police to Lloyd's body and his own chilling catalogue of photographs and undergarments taken from his victims' homes.

"I never thought it would pay off that way,” Giczi says, "but that's the best payment I could have had.”