The Harris County, Texas, sheriff's office says it is investigating a deputy caught on video pulling a gun on a motorist and threatening to kill him. George Dickerson says a deputy riding a motorcycle in front of him slammed on his brakes, forcing him to also stop suddenly. There was a second deputy, also riding a motorcycle, behind Dickerson. Dickerson said that second deputy got angry with him and pulled his gun on him. Neither of the deputies was named by local media.