Laura Wallen was pregnant when police say her boyfriend killed her over Labor Day weekend, and buried her body in a shallow grave on a Montgomery County farm.
Tyler Tessier, 32, has been charged with first-degree murder in her death. But Montgomery County State's Attorney John McCarthy said it's "highly unlikely" Tessier will face additional homicide charges for the death of the unborn child.
Under Maryland law, prosecutors may bring murder or manslaughter charges in the death of a viable fetus — one with "a reasonable likelihood of … sustained survival outside the womb."
Wallen, who taught at Wilde Lake High School, was four months pregnant at the time of her death.
"If there was an argument that the child was viable at the time of the homicide, then the law would support the potential of an additional homicide charge," McCarthy said. "The facts we do have suggest we're not going to get there."
A fetus is generally considered viable at around 24 weeks, said Dr. Fernando Mena, chief of neonatology at MedStar Franklin Square Medical Center. The baby's chance of survival outside the womb at that age is about 50 percent. A full-term pregnancy is 40 weeks.
Nearly 40 states have fetal homicide laws on the books.
In what may be the most famous use of a fetal homicide law, California prosecutors charged Scott Peterson in the deaths in 2002 of his wife, Laci, and their unborn son.
President George W. Bush signed the federal Unborn Victims of Violence Act, known as "Laci and Conner's Law," in 2004.
Maryland passed its law in 2005. It was first used about two and a half years later. David Miller of Baltimore County was convicted of killing a pregnant woman and the pair's unborn child in a shopping center parking lot. Elizabeth Walters was 32 weeks pregnant when Miller shot her. The baby girl was to be named Olivia.
Miller was married to another woman when he killed Walters, a detail reminiscent of the case of Tessier and Wallen.
Police say Tessier was engaged to another woman as he and Wallen were expecting a child together. Both women believed they were dating Tessier exclusively, police say.
Wallen was reported missing on Sept. 5 after she missed the first day of school at Wilde Lake. Police found her body Wednesday in a shallow grave in a Damascus field.
Tessier was arrested and charged with first-degree murder in her death. A judge ordered him held without bond pending a return to court Oct. 13.