David Barlow was set to leave lawyering in the big city behind when politics came calling.

After 10 years working on class-action lawsuits and high-profile white-collar crimes cases at Chicago-based Sidley and Austin — the same firm where President Barack Obama and his wife, Michelle, spent time practicing law — Barlow, a native Utahn and BYU grad, was ready to return to the Beehive State to raise his family.

But before he could make the move, Sen. Mike Lee, R-Utah, persuaded Barlow to serve as his chief counsel in Washington, D.C. That led to Barlow’s latest appointment as U.S. attorney for Utah, announced earlier this year. After several weeks in office, Barlow has adjusted to his new role and on Friday vowed to pursue justice while leading federal prosecutions for an office that has been waiting for a presidentially appointed boss to take the helm since December 2009.

Barlow, 40, was sworn in Friday at Salt Lake City’s federal courthouse, where colleagues praised his legal abilities. U.S. District Court Judge Ted Stewart presided over Barlow’s oath of office, while Barlow’s wife, Crystal, and the couple’s four children looked on.

Barlow borrowed a quote from George Sutherland, the only Utahn to serve on the U.S. Supreme Court, when describing what he believes his role should be in serving as U.S. attorney.

"To see that guilt shall not escape or innocence suffer," Barlow said, referencing Sutherland’s comments in the 1935 case Berger vs. U.S.

"It is profoundly satisfying to wake up each morning and to know my job is to see that justice be done," he added.

Barlow was introduced by Sens. Orrin Hatch and Mike Lee, who supported his nomination and confirmation, as well as BYU professor of political science David Magleby and attorney Michael W. Davis, of Sidley and Austin.

Lee joked that he felt bad about steering Barlow into politics because Barlow had enjoyed success at Sidley and Austin. Lee said "ask Barlow" became a catch phrase in his office because Barlow easily bridged the issues between law and politics with "impeccable judgment."

Magleby recalled Barlow as an ambitious undergrad at BYU who finished first in his class with a 4.0 GPA in 1995, before he went on to Yale Law School.

Barlow’s credentials include being awarded a Harry S. Truman Scholarship and being named as USA Today ’s 60 most outstanding college students, in addition to numerous prestigious law internships and externships.

Davis, who hired Barlow at Sidley and Austin, said he was leery of hiring him because he feared Barlow would be a "know-it-all" because of his flawless resume.

Davis said he was pleasantly surprised to realize Barlow made efforts to learn from others and likes to laugh. He said Barlow can recite lines from Plato, Aristotle and complex legal opinions — and just as readily can pull quotes from the 1987 comedic fairy tale "The Princess Bride."

"He takes work seriously but doesn’t take himself seriously," Davis said. "Our loss is your gain. He will serve the bench ... and the people of Utah very well indeed."

mrogers@sltrib.com

Twitter: @mrogers_trib