Sometime between 1920 and 1930 Tom began working as a salesman for a flour mill but by 1940 he had joined the Owsley County Sheriff's Office and worked as a policeman. He was shot and killed while attempting to arrest a man for causing a disturbance near New Hope Kentucky.
His memorial page on the Officer Down website describes his murder:
"The suspect immediately opened fire on Deputy Pendergrass as he stepped from his car, striking him in the chest with a shot from a .22 caliber. Despite being mortally wounded, Deputy Pendergrass returned fire, fatally striking the suspect.
Deputy Pendergrass attempted to drive himself to seek help but succumbed to the wound approximately two miles away.
Deputy Pendergrass was survived by his wife, four sons, four daughters, and two brothers. One of his brothers served as a detective with the Detroit, Michigan, Police Department."
|William Thomas Pendergrass Death Certificate; image courtesy of|
He was the third Owsley County Deputy Sheriff to lose his life in the line of duty.
Tom was interred in the family cemetery in Owsley County. His son, Willard H. Pendergast, and daughters Hazel Marie (Pendergrass) Bowman and Reba Pendergrass predeceased Tom. His wife, Maggie, never remarried and died on 19 December 1973 at her home in Preble County, Ohio. She was also interred in the family cemetery.
 The name of the suspect was Oscar Becknell, son of John W. and Jerushia Alice (Evans) Becknell. He was 47 years old and a World War I veteran when he was killed by Deputy Sheriff Pendergrass.