In 2000, when Wisconsin began collecting DNA from every convicted felon, Walter Ellis was in prison for beating his girlfriend with a hammer. According to state officials, he bribed another inmate to have his mouth swabbed and give the sample as Walter Ellis. The state Department of Justice noticed that the sample duplicated one already on file from the other man, but no one told the Department of Corrections that it still had nothing from Ellis. When analysts ran DNA from one of the north side killings in 2003, nothing matched. "If they would have got his DNA when they were supposed to get it, maybe my cousin would still be here," Sarah Stokes said later. Her cousin, Ouithreaun Stokes, twenty-eight, was found beaten and strangled in an abandoned rooming house in April 2007, the last of the seven women.
Ellis was born in Milwaukee on June 24, 1960, one of six children of LeRoy and Mattie Ellis. He was a bully as a child, quit school after the eighth grade in 1974, and was arrested for the first time that August, at fourteen, for robbery and attempted murder. What followed was thirty years of arrests: theft, robbery, drugs, extortion, attacks on police officers, a carjacking, a drug ring called the Brothers of the Struggle, a federal sentence served in Minnesota. In the early 1990s he became a police informant after reporting corruption at a halfway house, and for several years that status shielded him from charges, including assaults on girlfriends, one of whom he stabbed with a screwdriver. He was dropped as an informant in the late 1990s and served three years for reckless endangerment, and in July 2001 he came home to Milwaukee and worked as a laborer.
The women were killed within about three square miles of the city's north side. Most were sex workers. Deborah Harris, thirty-one, was strangled and dumped in the river on October 10, 1986, and Tanya Miller, nineteen, was strangled the next day. Irene Smith, twenty-five, was strangled on November 28, 1992. Florence McCormick, twenty-eight, was found strangled on April 24, 1995, and Sheila Farrior, thirty-seven, was found on June 27 of the same year. Joyce Ann Mims, forty-one, was found strangled on June 20, 1996. All seven were strangled, by hand or with a rope or piece of clothing; one had also been stabbed. The police treated the killings as unrelated until May 2009, when a cold case review showed through DNA that one man had committed them all.
The missing sample was traced, and in late August 2009 Ellis was ordered to give a new one. When he failed to report, police got a warrant, searched his apartment and took his toothbrush. The DNA on it matched semen on six of the victims and blood on a can of pepper spray found at the seventh scene. On September 7 officers found his maroon 1994 Buick Century in Franklin and arrested him at a motel there. The police chief, Edward Flynn, said the case had been solved "with shoe leather and science." The statewide audit that followed found that about 12,000 samples owed by offenders, roughly a tenth of the database, were missing.
The DNA also freed two innocent men. Chaunte Ott had been convicted in 1996 of the murder of Jessica Payne, sixteen, killed on August 30, 1995, on the strength of witness testimony alone, and served thirteen years before the Wisconsin Innocence Project showed that his DNA matched nothing found on her. Charges were dropped and he was released in 2009. Ellis was a suspect in Payne's death, but because her throat had been cut, unlike the others, prosecutors did not charge him with it. In May 2010 his DNA was matched to the 1998 murder of Maryetta Griffin, for which William Avery had been convicted in 2005, and Avery was exonerated. Ellis was also suspected in the 1994 killing of Carron Kilpatrick, thirty-two, whose accused killer, Curtis McCoy, had been acquitted.
Ellis first pleaded not guilty, and trial was set for April 2011. In February he took a plea agreement instead. On February 24, 2011, he was sentenced to seven consecutive life terms without parole. Under an interstate compact he was sent to the South Dakota State Penitentiary in Sioux Falls in June 2011. The Wisconsin Supreme Court declined to hear his appeal in 2013, and on December 1 of that year he died of complications from diabetes, at fifty-three.