Abusive boyfriend convicted of setting house on fire, killing mother and grandmother

(MARIETTA, Ga. — Feb 14, 2025) — A Cobb County jury has convicted Robert Colt Smith, 32, of two counts of felony murder and first-degree arson for setting a house fire that killed Andrea Nall, 52, and Michelle Lacroix, 74. The jury also found Smith guilty of aggravated battery and aggravated assault for brutally beating Nall’s daughter before the fire.
Superior Court Judge Kellie Hill sentenced Smith to two life sentences plus 20 years in prison.
“This case is a tragic reminder of how domestic violence can escalate to devastating consequences,” said District Attorney Sonya F. Allen. “Thanks to the hard work of our prosecutors and law enforcement, justice has been served, and this defendant will never harm another person again.”
On Feb. 14, 2022, Smith violently attacked his then-girlfriend, 19-year-old Carolyn Parmalee, leaving her with severe black eyes swollen shut and a shoe print on her face. He was arrested and later released on bond under a no-contact order. Despite this, he convinced Parmalee to continue their relationship.
A year later, Parmalee was hospitalized again after another assault. Two weeks later, on Feb. 26, 2023, she was hospitalized a third time due to Smith’s violence.
Parmalee’s mother, Andrea Nall, tried to protect her daughter by seeking to have Smith’s bond revoked for violating the no-contact order. Shortly after learning of this, Smith set fire to a vehicle parked outside her home, which spread to the house.
In the early morning of March 12, 2023, Smith went to Parmalee’s home on Janet Lane in Austell with cans of spray paint. He used the paint as an accelerant to set fire to a Honda CRV parked under the carport. The vehicle ignited instantly, spreading flames to the carport and the house.
The two victims, Andrea Nall and her mother, Michelle Lacroix, alongside eight pets, were inside. All died of smoke inhalation as the home was engulfed in flames.
“This community was robbed of two amazing women who opened their home as a refuge,” said Senior Assistant District Attorney Jared Horowitz, who prosecuted the case alongside Senior Assistant District Attorney Stephanie Green. “These two mothers did what any parent would—protect their children from an abuser. But this defendant used fire to seek revenge. Justice prevailed today, and his reign of terror is finally over.”
District Attorney Allen would like to recognize the Cobb County Police Department, Cobb County Emergency Services, the Bureau of Alcohol, Tobacco, Firearms and Explosives, and all those who helped bring the case to justice.
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