Donald Murphy (born 1944) is an American serial killer, sex offender and bank robber, convicted of murdering two prostitutes in Detroit in 1980. During this time, several similar murders occurred in the city, presumably committed by two or more killers operating in the area, with Murphy himself confessing to committing at least six of them. However, he was convicted of only two with the available evidence, and sentenced to 15–30 years imprisonment for each murder.
 Murphy was born in Detroit and was later the father of six children. Murphy committed his first known crime on February 10, 1967, when he was convicted of "carnal knowledge of a female" and sentenced to six months imprisonment at the Detroit House of Correction, in addition to being fined $1,000. Two years later, on July 28, 1969, he was arrested for unarmed bank robbery and sentenced to eight years of federal imprisonment, but was paroled on October 10, 1972. Only a year later, he was again arrested for attempting to burgle a business place, and given a one-to-five year term at the Michigan State Prison on February 13, 1974. He was paroled 10 months later and remanded to the custody to the U.S. Marshall's Office, completing his prison term on May 12, 1976.
 Between the late 1970s and into 1980, a total of 18 prostitutes were killed in and around Detroit. The investigating forces theorized that at least two serial killers were operating in the area, as some victims were killed in different ways and in different locations than others. Of the latter murder series, the victims connected to Donald Murphy were as follows:
 In November 1980, 23-year-old David J. Payton, a girls' basketball coach from Highland Park, was arrested for soliciting prostitution services from undercover officer Anita Hicks. Due to his previous minor offences, he was publicly named as a suspect for four of the murders (of Woods, Rembert, Burks and 24-year-old Rosemary Frazier, found nude and strangled on May 30), as well for an unrelated rape. For a brief period, he was also questioned for a series of murders in Cincinnati, Ohio, where he used to play for the Xavier University's basketball team. Initially remanded to the Wayne County Jail, Payton was investigated for the murders and the rape, much to the disbelief of his friends and family, who were convinced the police had arrested the wrong man.
 During interrogations, Payton falsely confessed to the murders under pressure from investigators, who questioned him for 56 hours straight, refused to let him see his lawyer, and even took away his contact lenses. However, after Murphy confessed to nearly all of the same murders, this caused a short-lived confusion, which was later cleared via physical evidence putting Murphy at the crime scenes. In the end, Payton was acquitted of all charges, and two years later would sue the Wayne County Prosecutor's Office, as well as the Detroit and Highland Park Police Forces, in a $15 million lawsuit for slander.
 On December 13, then-24-year-old Cheryl Harris was walking home towards Oak Park, when an unfamiliar man drove up to her and offered her a ride. She declined, but was reassured when the stranger told her he was a police officer. The mood shifted quickly, as the "officer" drove past her house and down the street, causing Cheryl to attempt leaping out of the car. He held her at knifepoint and told her to undress. Harris began fighting back, biting her assailant in the chest, which caused him to use her sweater belt to choke her into unconsciousness. She was sexually assaulted and left for dead on the streets. Nude and with her hands tied to her back with pantyhose, Harris nevertheless managed to crawl towards a house and alert the homeowner, who called the police. She described her attacker and his vehicle in detail, which led to the arrest of 36-year-old Murphy, of Schaefer Avenue, a convicted sex offender and bank robber who had been on probation since April 7 on a concealed weapons charge.
 After a search was conducted on his property, the pickaxe handle used in the Warren murder was located in the trunk of Murphy's car. Hair samples on that handle also matched those of Betty Rembert. Not long after, Donald admitted to killing at least ten prostitutes in the city, including three previously assigned to Payton. According to anonymous sources, all of the killings occurred while Murphy was heavily intoxicated, and had only hazy memories of the events. On the mornings after, he would awake feeling that he had done something terrible, initially in disbelief, but would later realize that he had killed them after reading or watching the news about the crimes. Despite his confessions, Murphy could only be charged with the deaths of Warren and Knott, as the others simply lacked enough evidence.
 On January 7, 1982, following an hour-long talk with his mother on the phone, Murphy formally confessed to the murders of Warren and Knott as part of a plea bargain. When addressing the court, he quoted passages from the Bible and asked for forgiveness from God and the victims' family members. He was convicted of the two slayings, and received concurrent terms 15 of 30 year for each murder. As a result, from the investigation into the prostitute murders, the Detroit Police Department's Homicide Squad transferred out two officers, Lt. Richard Ridling and Det. Jimmy Harris, and respectively replaced them with two others from the Armed Robbery Unit and the Control Center, Lt. Alfred Brooks and Lt. Robert Prince.
 It is unknown whether Murphy, whose sentence has since expired, died in prison or was released.