Tex. Nat. Res. Code § 88.055

If the gas from a well producing both oil and gas is not trapped and used and the gas is capable of being burned in a flare, no person owning, leasing, operating, or controlling an oil property in this state may produce oil from the well at any time without simultaneously and continuously burning a flare to consume all gas that otherwise would be permitted to escape into the open air. The Railroad Commission of Texas shall have the authority to grant exceptions to this section.