McCulloh joined the staff of Gonzaga University in 1990. He initially worked as a student affairs employee in the residence life department. He taught undergraduate psychology part-time for a number of years while serving in a variety of administrative positions, including dean of student academic services, dean of student financial services, associate academic vice president, and vice president for administration and planning. McCulloh also served as the interim academic vice president from 2007 until becoming interim president in 2009. During his career as an administrator, he worked on a number of projects including development of Gonzaga's first office for students with disabilities, the implementation of an integrated computing information system, building new on-campus housing, chairing the decennial regional accreditation self-study, and the creation of a plan for Gonzaga's future development.
President of Gonzaga
McCulloh was named interim president of the university by Gonzaga's board of trustees on April 17, 2009. His appointment was effective on July 15, 2009. McCulloh was elevated from interim president to president of Gonzaga by the board of trustees on July 16, 2010. His promotion made McCulloh the university's first permanent, non-Jesuit to hold the office in Gonzaga's history. During his tenure, Gonzaga University has had a series of changes in leadership and undertaken a number of significant projects. In service of providing valuable, high quality education, in summer of 2013 the university began construction of a 168,000 square foot University Center. This project supported by what was then the largest gift in Gonzaga's history. The John J. Hemmingson University Center opened in 2015 and provides a technologically advanced environment reflective of the core components of a distinctly Jesuit education. A LEED Gold certified facility, it prominently features the Center for Global Engagement, reflective of the institution's commitment to international education and study abroad, as well as numerous services to host and support student learning and functions to support student development. The Center also hosts the new, primary residential dining facility for the campus. Gonzaga recently announced a significant bequest, which is supporting construction of the 52,000 s.f. Myrtle Woldson Center for the Performing Arts. Recognizing the importance of healthcare as a vital growth area as well as a local economic development focus, McCulloh has worked to support significant developments, such as the launch of a new School of Nursing and Human Physiology in response to growing demand, as well as the creation of a Spokane medical education partnership with the University of Washington. In September of 2018, Gonzaga University concluded its most ambitious fundraising campaign to date which, when announced in 2015, had a goal of $250 million. The total raised was $355.4 million, of which $110 million was dedicated to fund scholarships for students. Gonzaga's part in the Catholic sex abuse scandal came to light during McCulloh's term as President, when an investigative report found that priests with histories of sexual abuse were quietly sent to live on the university campus, shielding them from liability and prosecution. McCulloh said he had no knowledge of the campus being used to hide abusive priests, and that he understood why some were incredulous that he could have not known. McCulloh established a commission to investigate the University's role and actions, and, in a public letter, said he was horrified by the abuse by priests, and expressed his feelings of "feelings of sadness, disgust and betrayal" upon learning that they had been housed on campus.