Maine Mom Was Murdered by Her Teen Son and His Friends Over Argument About Marijuana

A Maine teenager who killed his mother after she confronted him and his two friends about stealing her marijuana was sentenced to 33 years in prison Thursday.

In November, Lukas Mironovas, 16, pleaded guilty to murder and conspiracy to commit murder in the April 21, 2018, death of his 47-year-old mother Kimberly Mironovas.

Prosecutors alleged Lukas, then 15, and his two friends William Smith, then 15, and Thomas Severance, then 13, concocted a scheme to kill his mother after she came home from beauty school and accused them of stealing some of her marijuana and then refused to give Smith and Severance a ride back to Massachusetts, where they lived.

“First, they were going to steal the car and drive themselves to Massachusetts,” Lukas Mironovas’ defense attorney Pamela Ames tells PEOPLE. “But they discarded that because she would be able to find her car and they would get caught.”

The teens then planned to drug her wine with prescription pills and slit her wrists to make it look like a suicide but decided against that plan because the pills didn’t dilute sufficiently.

“Then they come up with the plan they will strangle and stab her and stage it to look like a suicide or a home invasion, and she got killed in that,” Ames says.

Ames says at one point Lukas allegedly considered not going through with the killing when his mother told them she indeed would drive the two teens back to Massachusetts.

Lukas Mironovas | Joe Phelan/The Kennebec Journal via AP
Lukas Mironovas | Joe Phelan/The Kennebec Journal via AP

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Severance, she says, backed out of the plan.

“It was Mr. Smith who was the ringleader,” says Ames. “He was the one who wanted to go through with it, no matter what.”

Prosecutors said fifteen minutes after Kimberly went to bed, Smith and Lukas snuck up to her bedroom.

Both boys choked her and Lukas stabbed her in the throat repeatedly.

“Lukas stabbed his mother repeatedly in the neck with a knife he had brought from downstairs,” said Assistant Attorney General Meg Elam, at an earlier plea hearing. “According to medical examiner Kristin Sweeney, the cause of Kimberly Mironovas’ death was the concurrent cause of strangulation and multiple knife wounds to her neck.”

Smith’s attorney, Walter McKee, says it was Lukas who was the instigator, not his client.

“He was the one who took a knife and stabbed her in the neck, not William,” McKee tells PEOPLE. “What was clear but for Lukas fixated on it it never would have happened.”

Smith, he says, feels “tremendous remorse” over the slaying.

According to prosecutors, after the murder the teens told police that an intruder killed Kimberly but later admitted to the crime.

Ames says Lukas was kicked out of “every school system” in Massachusetts before he and his mother moved to Maine.

In the days leading up to the murder, Ames says Lukas, who had also been kicked out of school in Maine, wanted to visit his two friends in Massachusetts but instead Kimberly decided to bring them to Maine.

“Kimberly did everything she could do,” she says. “If she hadn’t gone down to get Smith and Severance I don’t think this would have ever happened. You can’t blame her she was trying to do something. Lukas was isolated. He had nothing going on in his life.”

Severance, 14, pleaded guilty to conspiracy to commit murder in the homicide and is incarcerated at the Longcreek Youth Development Center until the age 21.

Smith, 17, pleaded guilty to murder and conspiracy to commit murder and was sentenced to 28 years in prison. He is serving his time at Long Creek until he turns 18 and then will be housed in Maine State Prison.