Mark Putnam was first FBI agent to commit murder when he killed Susan Smith: ID investigates

Investigation Discovery is looking into the brutal murder of Susan Smith from Pikeville, Kentucky, in 1989.

Susan had been an FBI informant, and the police first assumed that a criminal gang had murdered her; however, the real killer was her FBI handler, Agent Mark Putnam. Putnam is the first known FBI agent to have committed murder.

In 1987, the FBI decided to begin an investigation into bank robber Carl Lockhart, aka Cat Eyes, a career criminal from the small town of Pikeville.

Agent Mark Putnam was fresh out of the FBI Academy, and he wanted to make an impression on his superiors. It was through the investigation that he came across Susan Smith. The mother of two was married to a friend of Cat Eyes, and she was willing to help out the investigation.

Susan became an informant for the FBI, and Putnam was her handler. The case against Cat Eyes was successful, and he ultimately went to prison. However, in the meantime, the relationship between Susan and the married Putnam soon morphed into a sexual affair.

They reportedly would have sex in Putnam’s car whenever they met on secluded strip-mine roads. However, Putnam began to fear for his marriage and career, so he requested a transfer to Florida.

On June 8, 1989, Putnam had returned to Pikeville to attend to some casework. He made contact with Susan, and the pair drove to a rural area. Susan told him that she was pregnant with his child, and they began to argue.

Mark Putnam says he snapped and murdered Susan Smith

At some point, Putnam says he snapped because Susan was threatening to tell his wife about the affair, so he strangled her to death. He then threw her body into the trunk of his rental car. The following evening he dumped her remains off an old coal mine road about nine miles north of Pikeville.

Susan was reported missing a couple of days later by her sister. Initially, the investigators focused on her abusive husband and the criminals he and Cat Eyes had associated with. But as the investigation progressed, Putnam was starting to look like a possible suspect.

Putnam took and failed a polygraph test before offering the investigators a full confession of what happened to Susan. He also gave them instructions on how to locate her remains.

In June 1990, Putnam agreed to plead guilty to one count of felony manslaughter and was sentenced to 16 years in prison. Susan’s family were reportedly outraged that they were not consulted over the plea agreement as they had wanted him to stand trial for murder.

The former FBI agent only served ten years of his sentence. On his release, the now 41-year-old Putnam moved to Georgia, remarried (his first wife passed away in 1998), and began work as a fitness instructor.

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