The Rangers Take Over (movie, 1942)

Jim Steele spots Pete Dawson taking horses over the Mexico-Texas border, but Dawson has an alibi. A new group of recruits arrives at the Ranger station, among them Tex Wyatt, the son of Ranger Captain John Wyatt, whom he hasn't seen for many years. Captain Wyatt tells Tex that he is in the Rangers strictly on his own merit and there will be no favors played. He assigns Tex to pick up Dawson's trail, but orders that no arrest be made without proof.