U.S. District Court Judge Dale Kimball handed down the prison sentence Wednesday after hearing attorneys debate what type of sentence the 57-year-old should receive and testimony from the now 23-year-old Smart herself.
In handing down the life term, Kimball said the crime was "an unusually heinous and degrading set of circumstances. A life sentence reflects the seriousness of the crime."
Q & A
Why did it take so long to bring Mitchell to trial?
A lengthy state court battle over Mitchell's competency ended when a judge declared Mitchell incompetent to stand trial in 2008 and also ruled he couldn't be forcibly medicated to try to restore his mental health.
Federal prosecutors later filed charges and succeeded in having him declared competent with a different approach, using both mental health experts and lay witnesses, including some who had interacted with Mitchell at the Utah State Hospital.
How much time will Mitchell's wife, Wanda Eileen Barzee serve?
Barzee, 65, is currently serving a 15-year term at a Texas federal prison. A federal judge gave Barzee credit for the seven years she had already spent either at the Utah State Hospital or the Salt Lake County jail. Barzee's federal time is running concurrently with a one-to-15-year state conviction for the July 2002 attempted kidnapping of Smart's cousin. Barzee will be eligible for state parole in 2018, but she could remain in prison until 2024.
Read previous coverage of the Elizabeth Smart kidnapping trial, including her testimony.