Alberta Attorney General Doug Schweitzer says he's been questioned by the RCMP in their investigation into his party's leadership race.

"I personally am not under investigation," Schweitzer said Monday. "The RCMP told me that. They asked me about the leadership race and that was it. I'm not going to comment further."

Mounties are looking into whether voter fraud was committed in 2017 when the United Conservative Party picked its leader. Jason Kenney, who would go on to become Alberta premier, decisively defeated Schweitzer and former Wildrose Party leader Brian Jean.

Allegations have been raised that email addresses were fraudulently attached to party memberships to cast ballots.

During question period Monday, the Opposition NDP asked Schweitzer to confirm a CBC report that the RCMP had spoken to him. Schweitzer confirmed it.

NDP Leader Rachel Notley renewed her call for a special prosecutor from outside Alberta to handle the probe to avoid any interference or perception of conflict of interest.

Police work closely with prosecutors on investigations, and Alberta's prosecutors work for Schweitzer and Kenney.

"You must either appoint a special prosecutor or step aside," Notley told Schweitzer.

But Kenney and Schweitzer told the house that a special prosecutor is not necessary because they respect the line that divides the attorney general from prosecutors and police.

"Making sure we preserve the integrity and independence of our police and our prosecutions is paramount to the justice system. I take that very, very seriously," said Schweitzer.

"I learned from the RCMP that they wanted to talk to me on Saturday. And then I met with them on Sunday for a brief 30-minute discussion, answered their questions fully and they had no further questions for me."

Notley said outside the legislature that it is "jaw-dropping that we're not at a point where they are calling in a special prosecutor.

"(Schweitzer) is at least pretending that he doesn't understand the relationship between Crown prosecutors and police investigators."

At the time of the leadership vote, both Schweitzer and Jean expressed concerns that voter fraud had occurred, but the committee overseeing the vote said it found no such evidence.

Schweitzer won in Calgary-Elbow in the April 16 election in which the United Conservatives defeated the NDP. Kenney appointed him justice minister and attorney general.

Alberta's elections commissioner is also reviewing the leadership contest and has levelled fines over illegal funding for Calgary businessman Jeff Callaway, who was also a candidate.

Kenney has faced -- and rejected -- allegations that Callaway was a puppet who entered the race on Kenney's behalf solely to attack Jean while Kenney stayed above the fray.

In March, documents surfaced showing that the Kenney and Callaway campaigns shared talking points, attack ads and agreed on a date on which Callaway would quit the race to back Kenney.

Kenney had said such communication is normal in politics.