Alberta's newly elected United Conservative Party government is refusing to appoint an outside prosecutor to oversee RCMP investigations related to alleged voter fraud and illegal political donations that may affect Justice Minister Doug Schweitzer and Premier Jason Kenney.

On Thursday, Opposition leader Rachel Notley released a letter to reporters in which she asked deputy attorney general Phil Bryden to appoint a prosecutor from outside Alberta.

"It is an unprecedented situation that you have an active police investigation into something that touches on the interests and the conduct of both the premier and the attorney general," Notley told reporters.

"But that is what we have here. And so at the very least we absolutely must seek out independent — robustly independent — oversight of this process. And the only way to do that is from outside of Alberta."

But on Friday, Bryden denied the request.

"Police investigations are independent, including independent of government. By virtue of this, elected officials are not involved in operational decisions or investigations of police, including the RCMP," Bryden said in an emailed statement.

"As such, elected officials are not involved in directing a police investigation, nor do department officials need to take additional steps to ensure police independence."

Bryden said that, as is generally the case, if it is appropriate to involve a Crown prosecutor from outside Alberta, "that decision is made independent of the minister."

Although Bryden is independent of his minister, his statement is nearly identical to the one issued late Thursday by a press secretary for Schweitzer and Kenney.

Refusal ignores precedent, Notley says

Reached Friday, Notley said the NDP will make an issue of this, particularly during the legislature sitting later this month.

"We will continue to raise it because it goes to the heart of our democratic system, it goes to the heart of our justice system," she said.

Notley, who is a lawyer, told reporters on Thursday that while there is no doubt the RCMP will conduct an independent investigation, they often do so in consultation with a prosecutor. And ultimately, she said, that prosecutor will make a discretionary decision about whether to proceed with charges.

That fact highlights the need to ensure there is no opportunity for any kind of political interference, she said, adding that is impossible if the prosecutor is from Alberta and must answer to the "boss" — the minister — who ultimately employs them.

On Friday, Notley said the refusal ignores past precedent in this province and others of bringing in an outside prosecutor in cases that involve senior government politicians. And she said the statements from Bryden, and on behalf of Schweitzer and Kenney, ignore the fact that police often work with a prosecutor before charges are laid, particularly in complex cases such as this one.

Complaint to ethics commissioner

Notley on Thursday also released a second letter she sent to Ethics Commissioner Marguerite Trussler. Notley said she asked Trussler to investigate potential breaches of the Conflict of Interest Act by Kenney and Schweitzer as another means to ensure there is an independent investigation, in case her request to appoint an outside prosecutor was denied.

"Should that request (for an outside prosecutor) be honoured, it may well be that the request for your office's involvement becomes moot," Notley wrote in her May 2 letter to Trussler. "However, until that happens, we are deeply concerned for the integrity of the process that currently exists."

Notley specifically asked Trussler to consider potential breaches of sections 2, 3 and 4 of the Conflict of Interest Act. Respectively, they address: decisions that might personally benefit a member of the legislature; attempts to influence a decision; and the use of insider information.

By law, the ethics commissioner can neither confirm nor deny the existence of investigations.

Vote irregularity, illegal donations

Schweitzer, as justice minister and attorney general, is responsible for ensuring the independence of several ongoing RCMP investigations related to the UCP leadership race, in which he was a candidate.

Just hours after the United Conservative Party leadership voting process began in late October 2017, Schweitzer and fellow candidate Brian Jean tried to have the vote suspended over concerns about voter fraud. The party refused, insisting the process was secure.

But CBC News and other news outlets have revealed serious problems with the vote and the RCMP are now conducting criminal investigations in both Calgary and Edmonton.

In Calgary, documents revealed email addresses fraudulently attached to party memberships were used to cast ballots in the leadership vote. And people with suspect emails attached to their memberships confirmed they did not vote in the leadership race, and that their emails were different from the ones on the list.

The RCMP are also investigating allegations of illegal political donations to the UCP leadership campaign of Jeff Callaway. Documents obtained by CBC News show Callaway ran for the sole purpose of targeting Brian Jean on behalf of the campaign of Jason Kenney.

Alberta's elections commissioner so far has issued fines totalling $49,000 related to improper donations to Callaway's campaign and attempts to obstruct his office's investigation.

In April, RCMP executed a search warrant and seized a computer from an auto-repair business owned by newly elected Calgary MLA Peter Singh.

Singh's lawyer confirmed the computer seizure was part of the RCMP investigation into alleged voter fraud during the UCP leadership contest. Singh denied any wrongdoing.

Last week, CBC News revealed the RCMP voter-fraud investigation had expanded to Edmonton. At least three officers have conducted unscheduled interviews with UCP leadership voters from the South Asian communities in Mill Woods.

The officers were attempting to verify the identities and emails of registered voters, and whether they had actually voted.