A southern Alberta man has been sentenced to seven years in prison for killing the grandniece of former Social Credit premier Harry Strom.

Jerrison Herve Stopanski was originally charged with second-degree murder, but pleaded guilty to manslaughter in the death of 23-year-old Amy Lewis.

With credit for time served Stopanski's sentence amounts to 4.5 years.

Lewis was a nursing student at Medicine Hat College when she was last seen in June 2012. Despite several searches, her body has never been found.

Lewis' uncle Ray Strom said the family accepts the sentence.

"There are those who think that the decision was not adequate, perhaps not as harsh as could be," Strom said outside court.

"But we understand that we live within a society where we accept what the law has to say, what it has to offer and the protections that it gives to us as citizens."

Court heard that Lewis and Stopanski, 36, met through an online personal ad posted by the woman and arranged to exchange sex for cash.

Police were able to collect blood evidence from Stopanski's jeep with the DNA matching that of Lewis.

In coming to his decision, Justice Rodney Jerke told the court "there is more to this story than we know now."

Body never found

He said he was guided by the sentence handed down in another Alberta case where the body was never found.

In 1999, Dr. Abraham Cooper was convicted by a jury of killing an associate, Dr. Doug Snider, in Fairview. Cooper received a 10-year sentence.

Jerke said Stopanski's guilty plea and "deep and genuine remorse" were mitigating factors.

Ray Strom read a prepared statement by Lewis's father, Phil Strom, in which he suggested that based on his religious faith, he believes Stopanksi will someday face judgment from a higher power.

"True justice may not occur in this life. True justice is beyond this life. I'm reminded there is an ultimate justice who will judge all and it is not our place to determine whether justice was served here or not," he said.

"I can be assured true justice will be served someday even if some think it is not served now."

Stopanski's lawyer, Clinton Yarshenko, called Jerke's decision fair under the circumstances.

"When you can't shed light on the state of mind of the accused, the exact details of the death, it poses a difficulty for a sentencing justice," said Yarshenko.

Stopanski was also handed a life-time weapons prohibition and ordered to provide a sample of his DNA.