Brett was born in Montgomery, Alabama. He was raised in Corpus Christi, moving to Corpus in 1971. He received his Bachelor of Arts in Business administration from Baylor University in 1992. Brett obtained his law degree from Texas Tech University school of law in 1995, graduating with honors. While at Texas Tech, Brett was a member of the Board of Barristers, Texas Tech's honorary trial advocacy organization.
After graduating law school, Brett returned to Corpus to practice law in 1995 with the law firm of Barger, Hermansen, Mckibben & Villarreal, L.L.P. In 2000, Brett joined the law firm of Brin and Brin, PC and was made partner in 2001 and equity shareholder in 2002. In 2007, Brett joined two previous partners and formed Anthony, Peterson & Purnell, L.L.P.
Brett is admitted to practice before the state courts of Texas as well as the United States District court for the Southern District. He is a member of the State Bar of Texas, Corpus Christi Bar Association and the American Bar Association. He is also a member of the Texas Trial Lawyers Association (TTLA) and a member of the Reynaldo G. Garza American Inns of Court.