Born on his family ranch in Coryell County near McGregor, Texas, Neff attended McGregor High School. He received his bachelor's degree from Baylor University in Waco before spending two years teaching at Southwestern Academy in Magnolia, Arkansas. While in Magnolia, Neff taught Harvey C. Couch, who would later become a successful entrepreneur in Arkansas. Upon returning to Texas, he received his law degree from the University of Texas at Austin. While studying at the University of Texas Law School, Neff was a close friend of future U. S. Senators Tom Connally and Morris Sheppard. He served in the Texas House of Representatives from 1899 to 1905, including a term as Speaker. After returning to his law practice in Waco, he served as assistant county attorney and county attorney for McLennan County for six years.

Public Office in Texas

A progressive Democrat, Neff was a strong supporter of Prohibition and was instrumental in the development of the Texas State Parks Board. Pat Neff and his mother, Isabella Neff, donated the land which would become the first state park in Texas, Mother Neff State Park. Neff is notable for his pardon of folk singer Lead Belly in his last days as Governor. Neff was succeeded as governor by Miriam Wallace "Ma" Ferguson, who defeated a stronger-than-usual Republican nominee, George C. Butte, an American jurist who had opposed James E. Ferguson's line item veto of the 1917 University of Texas appropriations bill. After leaving the governorship, Neff served on the Texas Railroad Commission. Governor Ross Sterling then appointed Ernest O. Thompson of Amarillo to succeed Neff when he left the position to become President of Baylor University. Thompson served on the panel for thirty-two years and developed a reputation as an expert on petroleum issues.