Mayes is President of Middleton Oil Company, an independent oil and gas company that operates over 65 wells in South Texas and along the Gulf Coast, and is engaged in joint exploration ventures with other oil and gas companies. In addition to his work in the oil and gas industry, Mayes also runs his ranching, cattle, and farming operations in Chambers, Liberty, Jefferson, Kimble, and Webb Counties.

As a successful conservative small businessman, Mayes thoroughly believes in being involved in his community. Currently, he serves on the Board of Directors of First Liberty National Bank, the Chambers County Museum at Wallisville, and the Galveston Island Pachyderm Club, and recently served on the Board of Texas Public Policy Foundation, Empower Texans Foundation, and the Executive Committee of Texas Business Leadership Council.

Mayes Middleton is one of the most generous, charitable givers in our community. His efforts have rebuilt a church in Chambers County and donated a school in Galveston.

As a conservative Republican activist, Mayes is Secretary of the Chambers County Republican Party and recently co-founded the Chambers County Ethical Government Board that gathered 3,673 signatures to give taxpayers a say and stop a $57,000,000 Bond. He also led the charge to get Chambers County to adopt local debt and bond transparency rules and enhanced ethics rules for the benefit of all taxpayers and voters.

Mayes received a Bachelor of Arts in Plan II Honors, a Bachelor of Business Administration in Finance, and a Doctor in Jurisprudence from the University of Texas at Austin. He and wife Macy are members of Middleton Memorial Methodist Church in Wallisville. They have twin boys, Connor and Christian and are due with baby #3 in September. Mayes is from Wallisville, Texas.