Who is T. L. Johnson from The Dark Wind and what is their importance?

T. L. Johnson is the head of the DEA investigation into the failed drug delivery operation. Johnson believes that Chee is somehow involved, and he employs strong-arm tactics to try and get Chee to admit knowing where the missing cocaine is located. Johnson is described unscrupulous and ruthless, and when Chee goes to the Santa Fe prison, he learns that Johnson deliberately set up Tom West to be murdered by inmates as a snitch when he couldn't get him to reveal details about the impending drug shipment.