The Groundbreaking Trial of Penngrove’s Mary Ann Kenney
By John Patrick Sheehy & Jack Withington
To Sarah Looney, it looked like cold-blooded murder.
On the afternoon of July 18, 1872, Looney was standing outside her Penngrove ranch house watching William Cummings, a 20-year-old Irish laborer, leave the ranch with a wagonload of wood pulled by a team of horses. The wagon’s bed creaked as the wagon turned onto Adobe Road, heading for the Lavin Ranch half a mile to the south, where Cummings was regularly employed.
As the wagon passed Bannon Lane, Looney spotted John Bannon’s daughter, Mary Ann Kenney, walking across her family’s ranch toward Adobe Road. She was carrying a double-barreled shotgun in her hands. After jumping over the picket fence next to the road, the 17-year-old Kenney approached Cummings’ wagon from behind and leveled the shotgun at his back.
Looney couldn’t make out any conversation between the two, only the first shotgun blast, which missed Cummings. As Cummings turned in his seat, Kenney again leveled the gun and pulled the trigger. The second shot took off the top of Cummings’ head. The horses bolted, throwing Cummings back onto the wagon’s load of wood as they raced down the road.
Upon hearing the gunshots, Looney’s husband Robert came running out of the house in time to see the petite, five-foot Kenney walking back to the picket fence, where she carefully placed the shotgun on the top rail, took hold of two pickets, and vaulted over the four-foot high fence in a single bound. Picking up the gun, she calmly walked toward her parents’ house.
When the horses pulling Cummings’ wagon arrived at the Lavin Ranch, they found the gate closed. As they swerved to avoid it, the wagon lurched to one side, throwing Cummings onto the road. Ranch owner Tim Lavin found him there, breathing his last gasps, the top of his skull blown off.
By that time, John Bannon was driving his daughter in a carriage to Petaluma, where she surrendered to James Knowles, the town marshal. She explained to Knowles that Cummings left her no choice. Despite her warnings, he persisted in spreading lies and slander about her virtue, leading her to painfully separate from her newlywed husband Thomas.
Knowles placed her under arrest at his home until an inquest hearing could be held two days later.
At the inquest, Kenney appeared, her face hidden by a veiled Shaker bonnet. On the advice of her lawyer, she refused to testify. After listening to the testimony of Sarah Looney and a few character witnesses, the grand jury, with Robert Looney as its foreman, charged Kenney with first degree murder.
In terms of the law, the case was cut-and-dried. The only justification for homicide was either self-defense or the defense of one’s home. Neither seduction nor slander qualified. However, small town society at the time was merciless to young women whose reputations had been blemished by sexual scandal. Once disgraced, their options for marriage or honorable work often became severely limited.
As a result, in the court of popular opinion, or “highway law” as it was called, deadly retribution was viewed as justifiable in cases where a young woman had been seduced, sexually assaulted, or had her virtue slandered, assuming such retribution was carried out by one of the woman’s male relatives. Likewise, in cases where a husband discovered another man making love to his wife, or else boasting about making love to her, he was viewed as justified in killing the man. What made Kenney’s case unusual was that she had meted out the deadly vengeance herself.
The case attracted a flock of reporters from San Francisco. Their stories were carried on the wires around the country, setting off a national debate as to whether women had rights equal to men when it came to exercising highway law.
To add some celebrity sparkle, Kenney was identified in news reports as the niece of the famous Irish prizefighter and New York congressman, John Morrissey.
Kenney’s bail was set at $20,000 ($450,000 in today’s currency). It was posted by her father and 16 of his friends, including Petaluma coroner Kelly Tighe who had performed the autopsy on Cummings’ body. A barrel-chested, loquacious man with a booming Irish accent, Tighe operated the Brooklyn Hotel at the corner of Kentucky and Washington streets, site of today’s Hotel Petaluma. The hotel’s saloon, The Reading Room, was a popular gathering place for Irish immigrants.
On the Fourth of July, two weeks before Cummings’ murder, Kenney and her husband Thomas ventured into town to celebrate with friends. It was their first trip off the Bannon Ranch since their wedding five months earlier. Kenney’s parents had surreptitiously worked to keep the newlyweds secluded in Penngrove in an effort to protect them from Cummings’ vicious rumors.
Once in town, the couple split up, with Mary Ann going off to visit her girlfriends, and Thomas joining a group of fellow farmhands at The Reading Room. No sooner had he ordered a beer, than an inebriated Cummings sauntered up to the bar and began making salacious remarks about Mary Ann. Thomas threw his beer in Cummings’ face, and the two began to fight.
Thomas’s friends quickly separated them, hurrying Thomas out to the street, where they told him about the slanderous stories Cummings had been spreading—that his wife was a common prostitute with whom he, and other men he could name, had engaged in sex with since she was 12 years old.
On their carriage ride home that night, Thomas told Mary Ann what he had heard and asked if any of it was true. Bursting into tears, she denied it all as lies. Once they reached the ranch, Mary Ann’s parents encouraged the couple not to pay any attention to the foul slanders, that they would die out with time.
A week passed. During that time, Thomas brought the matter up with Mary Ann a couple of times, leading to fights between the couple. Finally, concerned that her husband did not believe her assertions of innocence, Mary Ann insisted they separate and not reunite until her name was cleared. Thomas reluctantly left the ranch to take a job working for the railroad in Sonoma Valley.
Kenney’s murder trial was held at the county courthouse in Santa Rosa. A number of her Penngrove neighbors who had known her since she was a child, testified to her modest chastity, describing her as intelligent, quiet and retiring, with a good-natured disposition. A bold horsewoman, she was known for her physical prowess, taking charge of plowing the fields of her family’s 140-acre ranch while still a teen.
William Cummings had come to live on the ranch five years before, when Mary Ann’s father hired him as a young ranch hand. He quickly became enamored with Mary Ann, asking her parents repeatedly for her hand in marriage, which they refused. Instead, another Irish laborer on the ranch, 30-year-old Thomas Kenney, won her heart.
After Mary Ann’s parents accepted his proposal to marry their daughter, Cummings left the ranch to work on the Lavin Ranch down the road. Following the wedding of Mary Ann and Thomas on Feb. 4, 1872, Cummings announced to friends he would dedicate himself to separating the couple before the year was out.
It took the jury only 50 minutes of deliberation to return with a verdict of not guilty in the case. Public opinion also sided with the verdict, extending their approval of a wronged woman’s right to deadly revenge. Wrote one local newspaper: “The tongue of her slanderer is silent forever. Not only she, but everybody else is safe from his malice.”
Three months after Mary Ann’s acquittal, Thomas filed a legal notice that his wife had abandoned him. “She left me,” he told reporters, “because she was conscience-struck.”
Mary Ann continued to live and work on the family ranch in Penngrove for the rest of her life. In 1899, at the age of 43, she married Jens Thomsen, a Danish chicken rancher, who joined her on the ranch until his unexpected death in 1906. She herself died in 1932 at the age of 76.
*****
A version of this story appeared in the Petaluma Argus-Courier, December 15, 2023, as well as in Jack Withington’s book, Looking Back at Penngrove, published in 2023.
SOURCES:
Newspapers
Cloverdale Bee: “Our Petaluma Letter,” August 3, 1872.
Daily Alta California: “Mrs. Kinney’s Case,” July 27, 1872.
Petaluma Argus: “Terrible Tragedy,” July 20, 1872; “The Cummings Murder,” July 27, 1872; “Examination of Mrs. Kinney,” July 27, 1872; “The Petaluma Tragedy,” July 27, 1872 (reprinted in the Weekly Butte Record); “Notice (of abandonment),” February 26, 1873; “Nonagenarian Passes Away,” January 22, 1917.
Petaluma Argus-Courier: “Loved Pioneer Woman Called,” January 28, 1932.
Petaluma Courier: “Local News: Bannon Estate,” December 31, 1891.
Petaluma Crescent: “The Petaluma Tragedy,” July 19, 1872 (reprinted in the Cloverdale Bee, July 27, 1872); “Verdict in the Petaluma Case,” July 20, 1872 (reprinted in the Daily Alta California, July 21, 1872); “Why the Woman Shot Her Slanderer,” July 27, 1872 (reprinted in the Weekly Colusa Sun).
Sacramento Bee: “Slander and Killing,” July 23, 1872.
San Francisco Chronicle: “The Petaluma Tragedy,” July 21, 1872; “Not Guilty,” October 27, 1872.
San Jose Mercury News: “Pacific Coast Items,” July 25, 1872.
Santa Rosa Press Democrat: “Sonoma Ranches Change Hands,” August 29, 1900.
Books & Documents
Thea Lowry, Empty Shells (Novato, CA: Manifold Press, 2000) p. 33.
U.S. Sonoma County Census: 1860, 1870, 1880, 1900, 1920, 1930.
