Rowe said it was difficult to put into words what Bartlett's loss meant.
"He certainly personified the true professional for American law enforcement, and especially right here in Texas law enforcement," he said.
Meanwhile, the 22-year-old gunman accused of killing Bartlett and wounding three other officers was also in critical condition at a Lubbock hospital, officials said.
Bartlett was shot after the Lubbock County SWAT team traveled to Levelland to help police there with a man who officials said barricaded himself in a residence and shot at police.
Texas Department of Public Safety spokesman Sgt. Johnny Bures on Friday said the Texas Rangers are now investigating the shooting and will present their findings to the Hockley County District Attorney's Office for filing of charges.