The convener of the Independent Senators Group is defending her decision to send Don Meredith to the United Nations status of women conference in New York while he was facing questions from the Senate ethics officer about his sexual relationship with a teenage girl.

Senator Elaine McCoy opted to send Meredith and Manitoba Senator Marilou McPhedran, a human rights advocate recently appointed by Prime Minister Justin Trudeau, as part of the Senate's delegation to the meeting on gender equality. The offer to send Meredith was rescinded after Conservative senators raised red flags about McCoy's pick.

McCoy said Tuesday that she made the decision before the ethics report was released.

"At that point, he was innocent until proven guilty, and that had been our stance all along," she said in an interview with CBC News. "We were still operating on that principle, as we would with any Canadian, you don't convict them before the verdict is announced.

"I stand by the decision to treat him as he was, as a full senator with the right to participate. I do."

Senator Elaine McCoy says she stands behind her decision to invite Senator Don Meredith to a UN Delegation on Women and Girls later this week. 2:38

Meredith left the Independent Senators Group — a grouping of senators who have left their partisan caucuses, but also senators recently appointed by Trudeau — after the ethics officer's report was released last week, detailing the Toronto-area senator's two-year relationship with a young woman called "Ms. M."

Lyse Ricard found reason to believe Meredith and Ms. M had intercourse three times, including once when the woman was 17 years old.

Meredith, 52, denies the allegations.

McCoy said she would have made different choices if Ricard had delivered her report earlier.

"She studied that for two years, for two years we've been waiting for her to establish the facts. What would you do in that circumstance? Until the facts are established, you have to assume everything is above board and everything is done properly. That is what I did," the Alberta senator said.

Meredith is also under two other separate investigations, including an inquiry about his allegedly abusive treatment of his staff.

The theme of the UN conference is women's economic empowerment in the changing world of work.

'Very offensive and objectionable'

Conservative Senator Don Plett said at the time it would be insensitive to send a man accused of having an inappropriate relationship with a young woman to the conference. He also said the Independent Senators Group was not entitled to send two delegates as the second seat was reserved for a Conservative senator.

"This is a status of women's conference and I found it very, very offensive and objectionable that Don Meredith, being under investigation for harassment of women, would be attending that conference," Plett said in an interview. "I said to Senator McCoy that he should absolutely not be going to that. I pointed out to her that it would be a terrible idea."

'Makes no sense at all'

The Manitoba Conservative senator, who serves as his party's whip in the Red Chamber, said the bad judgment is tied not only to the Independent Senators Group's decision to send Meredith to the conference but also its move to welcome him into their "caucus" in the first place.

"We expelled him from our caucus because of the investigations that he was under and the ISG accepted him into their caucus and named him as a member of their leadership team while he was under investigation on three different accounts of ethical misconduct or workplace harassment," Plett said. "I think that makes no sense at all."

Meredith briefly served on the Independent Senators Group's chamber co-ordination team, which also included senators Frances Lankin, Elaine McCoy and Pierrette Ringuette. His election to that position raised eyebrows when it was first announced in September. The ISG has refuted the characterization of his role as a leadership position.

As CBC News reported Monday, Senators are now looking for legal grounds to expel Meredith from the chamber if he does not voluntarily resign.