Commissioner Valentine graduated from Brigham Young University in June 1973 with a BS in accounting and economics and later earned a juris doctorate from the J. Reuben Clark Law School at BYU in April of 1976. He went to work for Howard, Lewis & Peterson in Provo soon after graduation and worked there until 2014 becoming a Managing Shareholder in 2000.
In 1988, Valentine was appointed to the Utah House of Representatives and was elected that same year. He served until 1998 when he was appointed to the Utah Senate. While in the House of Representative and House of Senate, he served on many committees and other appointments as as the Senate President.
Valentine was key in using a public-private partnership to purchase an interest in Rock Canyon, Utah. His actions are providing an open space easement for future preservation of his gateway to the rugged mountains east of Provo. Utah County also saw his efforts in the preservation of the Cherry Hill barn and farm, where he served as counsel for the Taylor family in the preservation of this historical site and green space. One if his greatest contributions has been that he was the legislative impetus for turning Utah Valley University into a university. UVU is the largest public university in Utah and educates thousands of students each year.
Valentine is the current Commissioner of Revenue and Chairman of the Utah State Tax Commission. He has served in Governor Gary R. Herbert's cabinet from 2014 to the present. He was elected to the Board of the Multi State Tax Commission (MTC) in 2015. Valentine was elected the Board of the Fedration of Tax Administrators (FTA) in 2016 and re-elected in 2018. Commissioner Valentine and his wife, Karen, are the proud parents of six children.