Laura Lynn Thompson

Left and Center: Laura circa, 1993

Right: Age Progressed to age 35

Vital Statistics at Time of Disappearance

Missing Since: January 7, 1993

Missing From: New Castle, Lawrence County, Pennsylvania

Classification: Endangered Missing

Date Of Birth: April 5, 1977

Age: 15 years old

Height and Weight: 5’6″ and 140 pounds

Distinguishing Characteristics: Caucasian Female, Red/Auburn hair, Blue eyes, Laura has a light colored birthmark on the back of her neck on her hairline

NCMEC Number: 777676

Details of Disappearance

Laura was last seen in New Castle, Pennsylvania on January 7th 1993. She was last seen en route to play cards with two friends. She never returned home and was never seen or heard from again. Her mother reported her missing within 48 hours of her disappearance.

Investigators initially assumed that Laura had runaway from home. Her case was classified as such by law enforcement for 17 years after she went missing. Her mother hoped that Laura might have left to build herself a better life. She has never runaway before and never showed an interest in doing so.

In July of 2010, the truth about what happened to Laura was revealed when a woman, Shannon Marshall, went to New Castle Police and implicated her soon to be ex husband and another man in Laura’s slaying. Shannon told police that her husband, Joseph Marshall, confesses that he killed someone in January of 1993.

He told her before they married and even offered to end their plans of marriage if she was too bothered by what he told her. He initially didn’t reveal the victims name but then told her it was a girl named Laura. She stated she was always burdened by her husbands confession.

She was prompted to find out more about his alleged victim and his involvement in the case since they were getting a divorce in 2010. She searched on the website of the National Center for Missing and Exploited Children and found Laura’s missing persons report. She then went to police and told them that her husband and his friend, Sean M. McDonough we’re responsible for her death.

The two were arrested and charged with killing Laura in September of 2010. They were the two friends that Laura was going to meet on the night of her disappearance. Marshall talked into a recording device that Shannon wore in order to gather incriminating evidence against her husband.

In the recording, he described how he, Sean, and Laura went to Sean’s mothers trailer and drank beer in Shenango Township, Pennsylvania. They then walked to a nearby cabin in the woods. He then stated that Sean began to behave erratically and talked in a satanic voice.

Sean proceeded to stab Laura repeatedly until she stopped moving. He then stripped Laura’s body of her clothing and had sex with her. Afterwards, he went back to the trailer to get a shovel. The two men then buried Laura’s body in a shallow grave.

In the next few months, Sean dug up Laura’s remains and discarded of them. He dug up her skull, mandible, and hands and discarded of them elsewhere. In the summer of 1993, Shannon accompanied Sean and Joseph to the area that they buried Laura in. She stayed in the car while they dug up Laura’s bones. They allegedly scattered her remains in a partially wooded field in Hickory Township. It’s also possible they were put in a ravine.

Forensic searches have been unable to uncover any trace of Laura’s body. Interestingly, when Sean was arrested in Louisiana for Laura’s murder, investigators found a long lock of red hair in his apartment. Laura had red hair when she disappeared. It’s unknown if the hair belonged to her.

Investigators have stated they don’t expect to recover Laura’s remains. A farmer threw his demolished barn and large amounts of earth into the ravine after Sean and Joseph disposes of her remains in that area.

Both men were charged with criminal homicide, murder, conspiracy, and abuse of a corpse. Sean McDonough was held in prison for 4 years after his arrest. They finally brought the resolution of the case forth. He was convicted of 3rd degree murder in connection to Laura’s death. He was sentenced to between 8 and 16 years in prison. He received credit for time already served.

In the same month, Joseph Marshall was convicted of Misdemeanor abuse of a corpse and was sentenced to 1 to 2 years in prison. He was released from prison after serving his sentence. All the other charges against him were dropped due to lack of evidence.

Shannon Marshall was never charged in connection to Laura’s disappearance. She and Joseph married in 1993 and gave birth to a son and daughter.

At the time of Laura’s disappearance, she was known to live a life of frivolity. She gave birth to a baby son when she was 14 years old. He was 9 months old when his mother went missing. He was put in foster care after Laura’s disappearance. Her mother became too sick and distraught over her daughters disappearance to care for him.

Laura was known to be friends with older adults. Sean was one of them and he convinced her to come and play cards with him and Joseph that night. They also invited one of Laura’s closest friends, Paul, who was 42 years old at the time. He declined the invitation due to an illness.

Laura’s body has never been found. Her case is still classified as that of an endangered runaway but foul play is strongly suspected in her case.

Investigating Agency

If you have any information concerning this case, please contact:

New Castle Police Department 724-658-4741

Source Information

The National Center for Missing and Exploited Children

The Charley Project

The Doe Network


New Castle News

CBS Pittsburgh

Pittsburgh Post-Gazette

New Castle News