- "Red John, shhh..."
- ―Last words of Sheriff Hardy
Dumar Tanner, more commonly known by his fake identity of Sheriff Ted Hardy, was a small town sheriff and one of Red John's accomplices, being the son of Orville Tanner, Red John's first known accomplice. Red John use the alias Roy Tagliaferro, a man from San Francisco or Hattuesburg. Hardy had the jurisdiction on Livingstone-San Angelo County. He was a recovering smoker and often seen chewing nicotine gum.
Tanner assisted Red John with the abduction of the twins, Emma and Maya Plaskett. They eventually kill Emma and stage her body using Red John's MO in order to catch Patrick Jane's attention. After the CBI are brought in to investigate the case, Tanner (introduced Sheriff Ted Hardy) pretends to assist them with the investigation.
As part of the investigation, Jane follows a letter addressed to "Roy Tagliaferro." This leads him to Rosalind Harker, who reveals that she had Thanksgiving with Red John, and a man named "Dumar Tanner" who brought her a stuffed animal. As Jane and Cho are looking at footage from the store where the stuffed animal was purchased, they discover that Ted Hardy is Dumar Tanner because of his nicotine habit.
Subsequently, Jane lures Tanner into revealing Maya's location by pretending to trust him. After it is revealed that Tanner was the one who kidnapped the twins, he also confesses he is the son of Orville Tanner; he claims that both father and son were close friends with Red John, but refuses to reveal anything more. Afterwards, he attempts to confess his love to Maya before being arrested. Before he is taken into custody, he kills one agent and attempts to shoot Lisbon. In order to protect her, Jane instinctively shoots him, wounding him lethally. Jane attempts to question him about Red John, but Tanner merely laughs at him before succumbing to his wounds.