Few Denverites in the early 1890s wouldn’t know the Millington murder case inside and out. At the time, a media frenzy around the salacious details of the case led to “excited public sentiment,” according to a February 1891 issue of the Fort Morgan Times. The case involved an alleged poisoning, the death of a famous local banking tycoon’s brother, accusations of adultery, a surprise change of trial venue and scandal due to suspects’ familial ties.
William Avery, who was the brother of Franklin Avery, founder of First National Bank and builder of the famed Avery House in Fort Collins, was murdered in 1891.
Officials assumed Avery died of a stomach ailment, but when his wife, Mary, married Avery’s business partner Frank Millington just 12 days after her husband died, Avery’s death raised more than just eyebrows.
Concerns of foul play arose after newspapers heard about the marriage and Avery’s body was exhumed and tested for poison.
After investigators confirmed Avery died of arsenic poisoning, they charged Mary Avery, Millington and Millington’s sister with the crime. Wild media coverage of the case caused the trial to be moved from Fort Collins to Denver with rumors that it might have also briefly moved to Greeley according to October 2016 coverage from the Coloradoan.
According to the Fort Morgan times article, “The social standing of the accused … and the fact that Millington’s sister, also accused, is a young lady, would naturally attract unusual attention.”
The Aspen Times also covered the case in February 1891 and noted the “illicit relations” showed at the trial between Mary Avery and Millington before Avery’s murder.
It’s unclear why exactly Mary Avery and Millington were found not guilty, but the testimony from a witness of a fight between Millington and Avery about the affair between Millington and the former Mrs. Avery shortly before his death and testimony about the nature of Avery’s death by a Dr. Lee failed to return a conviction, according to the Aspen Times and April 1891 coverage from the Grand Valley Star. According to the 2016 Coloradoan article, “The Avery family name has lived on in local history and is part of present-day Fort Collins with the imposing, historic Avery House on W. Mountain Avenue and the downtown Avery Block that wraps into Old Town Square.”
– Jess Brovsky-Eaker