A special prosecutor is recommending two men who were leaders of a religious sect in British Columbia serve time in jail for polygamy, but a defence lawyer says a conviction is all the punishment necessary.

Prosecutor Peter Wilson asked a B.C. Supreme Court judge Tuesday for a sentence of between 90 days and six months in jail for Winston Blackmore, and a term of one month to 90 days for James Oler.

Wilson said the offences were motivated by "sincerely held religious beliefs.''

"They are both, by all accounts, law-abiding, hard-working citizens, honest men,'' he said.

But Wilson said the sentences must denounce their crimes and deter others.

Winston Blackmore speaks with reporters outside court in Cranbrook, B.C., on July 24, 2017. He was guilty of marrying two dozen women that same month. Jeff McIntosh (Jeff McIntosh/Canadian Press)

He told Justice Sheri Ann Donegan that there are only two other convictions for polygamy in Canadian history, but because those cases took place in 1899 and 1906 they do not help in determining a sentence for Blackmore and Oler.

Blackmore's lawyer, Blair Suffredine, asked the judge to consider all possible sentences in the case, including an absolute discharge.

He said that would allow Blackmore to continue to work at his sawmill so he can support his family, and would not leave him with a criminal record, which could prevent visits to the U.S. where three of his wives live.

A conviction communicates to the community that polygamy is illegal and people who practice it may be prosecuted, Suffredine said.

"In my submission, that's all that's required here, is to tell the community, finally, that it's not protected and you take the risk that you'll be prosecuted,'' he said.

Suffredine said the unusual circumstances of the case need to be taken into account, including decades of investigations and court proceedings, as well as Blackmore's positive influence in the community and his religious beliefs.

"None of this was done with the intention of breaking the law. All of it was done through legitimate religious beliefs,'' he argued.

Winston Blackmore has been a leader in the Fundamentalist Church of Jesus Christ of Latter-day Saints, which condones plural marriage.

The judge found Blackmore, 62, guilty last July of marrying two dozen women, while Oler, 54, was found to have married five women.

Oler has not been represented in court by a lawyer. An amicus curiae, a so-called friend of the court, was appointed to ensure a fair trial.

Both men have been leaders in the Fundamentalist Church of Jesus Christ of Latter-day Saints, which condones plural marriage. They live in the small community of Bountiful in southeastern B.C.

Suffredine had earlier asked the court to stay the charges against his client after the guilty verdicts, arguing the law against polygamy infringed on Blackmore's charter rights to religious freedom.

Donegan dismissed the arguments in March, saying both Blackmore and Oler knew that entering into multiple marriages is illegal in Canada.

Blackmore family packs courtroom

In 1991, the RCMP completed a 13-month investigation into Bountiful by recommending polygamy charges against Blackmore and another man, but B.C.'s attorney general decided not to lay charges because of uncertainty over religious freedoms under the Constitution.

The B.C. Supreme Court upheld the polygamy laws in a 2011 reference case, ruling that a section of the Criminal Code banning plural marriages is constitutional. The court's chief justice said the harm against women and children outweighs concerns over protecting religious freedom.

Winston Blackmore, the religious leader of the polygamous community of Bountiful located near Creston, B.C., shares a laugh with six of his daughters and some of his grandchildren Monday, April 21, 2008 near Creston, B.C. (Jonathan Hayward/Canadian Press)

The courtroom in Cranbrook was packed for Tuesday's sentencing hearing, mostly with members of Blackmore's family. There were not enough seats to accommodate everyone and a video link was set up so the overflow crowd could watch the hearing from another courtroom.

During a break in the hearing, about three dozen of Blackmore's children and wives stood together outside the courthouse holding signs that read: "Families not felons" and "There is no cookie cutter for family."

The maximum sentence for polygamy under the Criminal Code is five years in prison.