Zipps formerly served as a United States magistrate judge of the same court from 2005 to 2011.

[2] From 1990 until 1991, she served as a law clerk for Judge William Canby of the United States Court of Appeals for the Ninth Circuit.

[2][3] From 1991 until 1995, Zipps worked as a litigation associate for the firm Molloy, Jones & Donahue in Tucson, Arizona.

[2][3] On June 23, 2011, President Barack Obama nominated Zipps to a seat on the United States District of Arizona, to replace Judge John Roll, who was killed in the 2011 Tucson shooting.

The United States Senate confirmed Zipps by unanimous consent on October 3, 2011.