Daniel King has probably one of the toughest jobs in America at the moment.

He's the main defense attorney for James Holmes, the 25-year-old accused of killing a dozen people at a Colorado movie theater last summer.

King, the chief trial deputy for Colorado's Office of the State Public Defender, said very little during Holmes' preliminary hearing this week, declining to call any witnesses or to present a closing argument.

Even though he has kept a relatively low profile in the Holmes case, a few facts can be gleaned about King from the public record.

He graduated from the University of Denver Sturm College of Law and has been with the public defender's office since September 1995, according to his LinkedIn profile.

Before law school he attended Boston College.

During his time as a public defender, King has represented some high-profile murder defendants.

He defended Sir Mario Owens, who was sentenced to death in 2008, HLN reported in July. Owens is one of only three people currently on death row in Colorado, The Associated Press reported in July.

Owens was accused of shooting Javad Marshall-Fields and his fiancee Vivian Wolfe to death in 2005, The Denver Post reported in 2008. Marshall-Fields was scheduled to testify in the murder trial of one of Owens' friends.

King also defended Jerry Nemnich in 2010, The Daily Sentinel reported in July.

Nemnich was convicted in 2010 of two counts of first-degree murder, 35 years after the death of 24-year-old Linda Benson and her 5-year-old daughter Kelley Ketchum, The Sentinel reported at the time.

While King's latest client, James Holmes, has yet to enter a plea, the public defender is expected to argue that Holmes is insane.

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