Shanna Garner was taken into police custody over accusations that she plotted the execution-style killing of her ex-husband Jared Bridegan.
The former Microsoft exec was fatally shot after stopping to move a tire from the middle of a Florida road, which investigators believe was intentionally placed.
Garner's current husband also denies involvement in Bridegan's murder.
Police body cam footage captured Garner being handcuffed and removed from her Washington home.
She maintains her innocence, but prosecutors allege she orchestrated her ex's coldblooded roadside slaying.
