In 1920, Kate Mooers (1853-1921), age 68, was affluent, the result of a recent divorce settlement from Dr. Charles E. Mooers, a physician and surgeon. She owned a small hotel in Belltown called the New Baker House, located at 2327 1st Avenue, and was part-owner of the Sophia Apartments at 409 Denny Way, where she lived. She wore expensive diamond jewelry and drove a big seven-passenger Westcott sedan but was well known for her miserliness. Kate Mooers was eccentric, petulant, short and balding, and estimated to be worth at least $200,000

The New Baker House was managed by Nora Mahoney, age 61, and her daughter Dolores Johnson, age 35, who maintained the rooms and collected the rents. During a visit to the New Baker House, Kate Mooers was introduced to Nora's son, Jim Mahoney. Following a short, if not peculiar courtship, they were married in a civil ceremony on February 10, 1921, using a wedding ring borrowed from Dolores Johnson, and took up residence in Kate's Denny Way apartment. Two months later, the Mahoneys started making plans for a belated honeymoon trip East to Saint Paul, Minnesota, and other cities. They planned to be away for one month.

On April 16, 1921, James E. Mahoney, a paroled convict, drugs his wife Kate, stuffs her in steamer trunk, and smashes her skull with a club. He then pours quicklime over her body. After locking the trunk and securing it with rope, he calls a transfer company to move it to a houseboat on Lake Union. There, the trunk is placed in a skiff and Mahoney rows to middle of the Lake Washington Ship Canal, just east of the University Bridge and throws it overboard. Kate Mahoney's nieces, suspecting foul play, report to police that she has mysteriously disappeared. After authorities search the ship canal for weeks, the trunk finally bobs to the surface on August 8, 1921, and is recovered by the tugboat Audrey. Mahoney, already in custody for forgery, is charged with his wife's murder. A King County Jury, after a 10-day trial, convicts Mahoney of first-degree murder on October 1, 1921 and sentences him to death. He is hanged at the Washington State Penitentiary in Walla Walla on December 1, 1922. Kate Mahoney's murder, which received national media coverage, was pronounced to be one of the most elaborately planned crimes of the decade.