An Ohio transgender woman has pleaded guilty to reckless homicide for exercising her 73-year-old husband to death in an apartment complex swimming pool.

Middlefield police say surveillance video shows 41-year-old Christine Newton-John pulling James Mason around the pool by his arms and legs and preventing him from leaving. Mason had a heart attack on June 2 just after the extended swim session.

Police Chief Joseph Stehlik says a deputy investigated the death because of previous complaints that Mason was abused. Newton-John pleaded guilty on Thursday. She faces up to five years in prison.

Mason was a longtime friend of his wife's family. He knew her as John Vallandingham before she had gender reassignment surgery in 1993 and changed her name. They married in Kentucky in 2006.