A Winnipeg man has lost a bid to overturn his conviction and 15-year prison sentence for running a child prostitution ring.

Following a jury trial last year, Darrell Ackman was found guilty of 14 prostitution, sex assault and child pornography charges involving vulnerable girls, most of whom were underage.

Ackman, who also ran unsuccessfully as a candidate for MLA in a 2013 Fort Whyte byelection, was arrested in 2012 and pleaded not guilty to all 17 original charges.

In his appeal, Ackman argued, in part, that his conviction on prostitution charges was unconstitutional in light of a 2013 Supreme Court of Canada decision — known as the Bedford decision — striking down prostitution-related Criminal Code provisions that were deemed to put sex trade workers at risk of harm.

But in a decision rejecting Ackman's appeal released this week, the Manitoba Court of Appeal ruled the Bedford decision was not intended to address the sexual exploitation of underage children, which remains illegal.

"I agree with the Crown that the underlying premise in Bedford was that prostitution was not illegal as it pertained to adults," Justice Diana Cameron wrote on behalf of the appeal court.

"On the other hand, prostitution involving persons under the age of 18 years was, and continues to be, illegal."

Ackman argued before the appeal court that he should serve a sentence no longer than 10 years.

Five of Darrell Ackman's seven victims were between the ages of 14 and 17 at the time of his July 2012 arrest. Two of the underage girls have since committed suicide. (CBC)

"The crimes that the accused committed were numerous and serious," Cameron wrote. "The accused's moral culpability was high.… In my view, the accused has not shown that he has an arguable case that the sentence was unfit."

Five of Ackman's seven victims were between the ages of 14 and 17 at the time of his July 2012 arrest. Two of the underage girls have since committed suicide.

Police began monitoring Ackman's activities after seeing videos he posted as Mr. JetzTV on YouTube and online ads for escorts.

Much of the Crown's case hinged on proving Ackman knew the girls he was selling as "escorts" were under 18.

Jurors were shown videos of Ackman having sex with a 14-year-old girl — who has since died — and a 17-year-old girl.

"I didn't know how old they were," Ackman testified at trial.

"I can only go on people's word and if they look adult and act adult and they are up all hours of the night … I just didn't believe these girls were underage."