Bathsheba Ruggles Spooner was born on February 15, 1746, in Sandwich, Massachusetts Bay. She was the daughter of Brigadier General Timothy Ruggles, a prominent lawyer who served as chief justice of the Court of Common Pleas in Worcester, Massachusetts, from 1762 to 1764. Timothy Ruggles was a Loyalist, meaning he supported British rule during the American Revolution. He did not sign the Stamp Act protest when he was a representative at the Stamp Act Congress in 1765. He even threatened to raise an army to protect Loyalist farms against Patriot forces, and he joined the British Army in Boston in 1775.

On January 15, 1766, Bathsheba married Joshua Spooner. Joshua was a wealthy farmer from Brookfield and the son of a prosperous Boston merchant. The couple lived in a two-story house and enjoyed a comfortable lifestyle. Bathsheba and Joshua had four children between 1767 and 1775. However, their marriage was troubled. Joshua Spooner was described as abusive, and Bathsheba developed a strong dislike for him.

By February 1778, Bathsheba Ruggles Spooner had begun actively plotting the murder of her husband. She first attempted to involve Ezra Ross in the plan. During a trip with Joshua to Princeton, Massachusetts, Ross carried a bottle of nitric acid intended to poison Spooner—allegedly provided by Bathsheba—but ultimately backed out and returned home without carrying out the attack.

Undeterred, Bathsheba soon found new accomplices. She invited two British soldiers, Private William Brooks and Sergeant James Buchanan, who had escaped from captivity, to stay at the Spooner home. During this time, she confided in them about her desire to see her husband dead and promised payment in exchange for their help. After updating Ross about the new plan, he returned to Brookfield on February 28.

On the evening of March 1, 1778, the plot was executed. Joshua Spooner returned home from a local tavern unaware of what awaited him. Brooks ambushed and bludgeoned him to death. Buchanan and Ross assisted in disposing of the body, which was thrown into the well on the Spooner property. Bathsheba then distributed her husband’s money and belongings to the three men and gave them a horse to aid their escape to Worcester.

The trio's actions quickly unraveled. Brooks and Buchanan spent the night drinking in town and flaunted Spooner’s possessions, including his personalized silver shoe buckles. They were arrested within 24 hours. Ross was found hiding in a tavern attic and immediately requested a confessor. All three implicated Bathsheba in their statements. She was arrested and charged with inciting, aiding, and procuring the murder of her husband.

Bathsheba and her co-conspirators were arraigned and pled not guilty. Their trial took place on April 24, 1778. The prosecution was led by Robert Treat Paine, a signer of the Declaration of Independence and soon-to-be Massachusetts Attorney General. Bathsheba was defended by Levi Lincoln, who would later serve as U.S. Attorney General under President Thomas Jefferson.

The court heard extensive testimony from the Spooner household servants and from witnesses who had observed the behavior of the conspirators. Brooks and Buchanan offered no defense, having signed full confessions. Ross, who had also confessed, claimed that he acted under emotional duress and lacked full knowledge of the murder plan. Lincoln argued that Bathsheba’s mental state was unstable and that her actions were irrational, particularly the absence of any plan to escape or conceal the crime.