Cox noted the review was done quickly and was not prepared to make any final legal determination on either candidate's eligibility without a more thorough inquiry.
The assessment comes a day before the 181-member Republican Party State Central Committee is scheduled to meet to vote to send the names of three of the seven candidates seeking the office to Gov. Gary Herbert, who will pick the replacement for Swallow, who resigned amid a yearlong scandal.
Utah GOP Chairman James Evans said he believes the report resolves the matter and Herbert has enough latitude on the timing of the appointment that residency won't be an issue even in Mumford's case.
"The issue of residency, that question has been answered," Evans said. "All our candidates would be able to meet that requirement by the time they take office before the Legislature convenes."
The Utah Constitution requires the attorney general to be a lawyer in good standing, age 25 or older, and a resident of the state for at least five years.
The requirement already forced one candidate, longtime federal prosecutor Brent Ward, to drop out of the race. Ward had headed a Justice Department obscenity task force in Washington, D.C., and had voted in Virginia, an act that under Utah law cost him is residency.
Ward said he believed he could have challenged the interpretation and prevailed in court, but didn't want to create more turmoil for an already-demoralized office.
Unlike Ward, Burns, who is a former attorney for Iron County, maintained his voter registration after he moved to Washington to be deputy drug czar under President George W. Bush. He voted in nearly every Utah election since 1990 and maintained either a home or apartment during that time.
Those facts outweighed evidence against Burns keeping his residency, for example that he moved his family out of the state and got a Virginia driver license.
Cox wrote that, based on the review, Mumford who is an assistant dean of admissions at Brigham Young University's law school has lived in the state for nearly five years. In Dec. 20, 2008, her family came to Utah with some household goods, staying with relatives and shopping for a home. She returned to California to give birth to a child Jan. 9, 2009, and the Mumfords closed on their home Jan. 26, 2009.
It could be argued, Cox wrote, that she became a resident Dec. 20. In that case Herbert could appoint her a week after the party's central committee makes its recommendations. If she is not eligible until Jan. 26, 2014, the governor would have to wait six weeks to select her.
The other five candidates seeking the office all appear to meet the residency requirements, Cox wrote.
Those candidates are:
• Sean Reyes, an attorney who lost to Swallow in a Republican primary last year.
• Bret Rawson, a reserve police officer and defense attorney who has worked extensively defending police officers for the Fraternal Order of Police.
• Michael Wilkins, a former Utah Supreme Court justice.
• Robert Smith, managing director of BYU's International Center for Law and Religion Studies.
• Brian Tarbet, the former adjutant general of the Utah National Guard who served as Swallow's general counsel and is currently the acting attorney general.
GOP meeting Saturday
Republican Party State Central Committee will meet Saturday, Dec. 14, at Salt Lake Community College's Larry H. Miller Conference Center, 9750 S. 300 West, Sandy, to select three candidates as possible replacements for John Swallow, who stepped down last week as Utah's attorney general.