Jurors in Edinburg earlier Monday convicted 33-year-old Jose Guadalupe Elizondo of murder.
Prosecutors say Elizondo was not on duty, in August 2010, when 49-year-old Fermin Limon was fatally shot outside his club near Alton.
Investigators say Elizondo had been thrown out of the bar, retrieved his government-issued gun from his truck and shot Limon.
Elizondo testified that the shooting was self-defense.
