The Greeneville Sun said prosecutors did not seek the death penalty for 21-year-old Ethan Self. He was sentenced to life with the possibility of parole.
Prosecutor Tony Clark said Ethan Self must serve at least 51 years before he is eligible for parole.
Self had admitted firing his father's service weapon on March 24, 2010, inside the family home, fatally wounding 46-year-old Greeneville police Sgt. Roger Self in the head.
Ethan Self declined to testify. He appeared stunned as Judge Kerry Blackwood read the verdict Thursday.
Defense attorney John T. Milburn Rogers had no comment after the sentencing.
The jury deliberated about four hours Wednesday afternoon and Thursday morning.