A judge who has decided that he will need to review the video evidence in a child pornography case is an example for others, a police investigator says.

Justice Robert Stack on Wednesday told a sentencing hearing for Mark White — a teacher who has admitted to making child porn and with luring a teenaged U.S. girl over the internet — that he will need to review the evidence itself before deciding an appropriate sentence.

Mark White, seen during an earlier court appearance, has pleaded guilty to child pornography and luring charges. (CBC)

White, who had taught English and worked as a librarian at Mealy Mountain Collegiate in Happy Valley-Goose Bay, was fired after he pleaded guilty to the charges.

Often with a guilty plea, a judge will proceed to sentencing even though the evidence collected during a police investigation is not brought before the court.

Sgt. Lana Prosper, an RCMP officer who works with the Centre for Missing and Exploited Children, said judges should look at pornographic evidence while deciding on a sentence.

"I think as law enforcement and for other people in the judicial system, it's part of our job," Prosper told CBC News.

"It's what the Canadian public expects of us. So we should be looking at every one of those images and videos every time."

Prosper says child pornography videos contain key information that could have an impact on sentencing.

White had pretended to be a teenage girl when he created a profile on the website Stickam. He used the site to contact a 16-year-old girl who lived in the state of Washington.

They chatted on MSN, and he tried to convince her to change clothes for him on her webcam.

When she said no, he threatened to post photos of her face on a naked woman's body.

The girl relented, and masturbated before the camera and used sex toys, all while White made a video recording.

The girl went to the police.

The next time White opened a chat conversation, a Washington detective was using her account.

White tried to convince her to go on webcam again, saying if she didn't he'd post the video of her on the internet.