Brock Smith graduated from Texas Tech University in 1971 with a Bachelor of Arts degree in Government and received his law degree from the same school in 1975. He initially entered private practice with Durant Clements of Bridgeport and became a partner in the firm after one year. In 1976, however, he left private practice to accept a position as an assistant district attorney in Decatur. In two years, he was appointed as the District Attorney for Wise and Jack Counties and was reelected two times before resigning in 1987 to return to private practice.

Brock served as a member of the Criminal Justice Division Advisory Board of Governor William P. Clements from 1979 to 1982, and as Director of the Texas District and County Attorney’s Association from 1983 to 1986.  During his service as District Attorney, he was also appointed as a Special Prosecutor in Cooke, Gregg, Parker, Stephens and Tarrant Counties.  He has also served as an Instructor for Weatherford College's Bridgeport Campus.  

Since 1987, Brock's practice has included criminal and general civil trial litigation.   His criminal case load includes both felony and misdemeanor representation with an emphasis on driving while intoxicated offenses and driver's license related cases. His civil practice includes general civil litigation, family law (including adoption, divorce and name change), will preparation, powers of attorney, medical powers of attorney, directives to physicians and related documents.  He also handles probate and estate matters as well as real estate document preparation and consultation.  Personal Injury representation and referrals in this area is also available.

Brock is a Member of the College of State Bar of Texas.  

In his spare time, he is active in the Boy Scouts of America. He currently serves as Adult Leader in the Boy Scouts of America and Longhorn Council of Texas. Brock is married to the former Angela Caraway, a native of Wise County, and has two sons: Russell and Cody.