The Oakland County Child Killer 2

After the discovery of Mihelich's body, authorities noticed similarities shared by her case and those of Stebbins and Robinson, and reports were released warning the public that a serial killer was possibly operating in the Oakland County area. The Michigan State Police led a group of law-enforcement officials from thirteen communities in the formation of a task force, devoted solely to the investigation into the killings of the three children.

After King disappeared, a woman told authorities that she had seen a boy with a skateboard (like King) talking to a man in the parking lot of the pharmacy that he visited on March 16, 1977. A composite drawing of the suspected kidnapper and his blue AMC Gremlin was released, and authorities questioned every Gremlin owner in Oakland County. Investigators created a profile based on witnesses' descriptions of the man seen talking to King—a white male aged between 25 and 35 with a dark complexion, shaggy hair and sideburns, who had a job that gave him freedom of movement and made him appear trustworthy to children, was familiar with the area and could keep children captive for long periods of time without rousing neighbors' suspicions.

The task force checked more than 18,000 tips, which resulted in about two dozen arrests on unrelated charges and the discovery of a multi-state child pornography ring operating on North Fox Island in Lake Michigan. The task force was unable to make much headway in the investigation, disbanding in December 1978, with the investigation being turned over to the State Police.

A few weeks after King's murder, a psychiatrist who worked with the task force received a letter, riddled with spelling errors, written by an anonymous author ("Allen") claiming to be a sadomasochist slave of the killer ("Frank"). "Allen" wrote that they had both served in the Vietnam War, that "Frank" was traumatized by having killed children, and that "Frank" had taken revenge on more affluent citizens, such as the residents of Birmingham, for sending forces to Vietnam. "Allen" expressed fear and remorse in his letter, saying he was losing his sanity and was endangered and suicidal, and admitted to having accompanied "Frank" as the latter sought boys to kill. He instructed the psychiatrist to respond by printing the code words "weather bureau says trees to bloom in three weeks" in that Sunday's edition of the Detroit Free Press, before offering to provide photographic evidence in exchange for immunity from prosecution. The psychiatrist arranged to meet "Allen" at a bar, but "Allen" did not show up and was never heard from again.

Archibald Edward Sloan, a child molester who victimized young boys in his neighborhood, became a person of interest after hair samples found in his 1966 Pontiac Bonneville matched hair found on the bodies of King and Stebbins, but the hair was not from Sloan himself. A witness claimed to have seen King being abducted by two men, one described as being in his late 20s and the other described as bearing a strong resemblance to serial killer John Wayne Gacy, who was allegedly in Michigan around the time of the killings. Gacy's DNA did not match DNA found on the victims' bodies.

Police in Parma Heights, Ohio arrested Ted Lamborgine, a retired auto worker involved in a 1970s sex ring that preyed on young boys in Detroit’s Cass Corridor. Out of the five men involved in the ring, Lamborgine was one only two living members of that ring when they were charged in 2006. Lamborgine faced 19 counts of sexually assaulting children, while his partner in the ring, Richard Lawson, faced 28 similar charges. On March 27, 2007, investigators told Detroit television station WXYZ that Lamborgine was considered the top suspect in this case. Lamborgine pleaded guilty to fifteen sex-related counts involving young boys rather than accept a plea bargain that would have required him to take a polygraph test on the Oakland County killings. He also rejected an offer of a reduced sentence in exchange for a polygraph on the case. In October 2007, the family of Mark Stebbins filed a wrongful death lawsuit against Lamborgine seeking $25,000. The lawsuit alleges Lamborgine, who lived in Metro Detroit in the late 1970s, abducted Stebbins and held him captive in a Royal Oak house for four days in February 1976 before smothering him to death during a sexual assault. Lamborgine has never been formally linked nor charged in the death of Stebbins. Attorney David A. Binkley has sought compensation, including funeral costs, for Stebbins' brother, Michael, but stressed that money is secondary.

Police reports obtained by Barry King included new revelations, including DNA testing of new suspects and the bloodstained ligature and sketch from Busch's apartment. Catherine Broad, King's sister, compiled an archive of investigation material as the case grew.

Upon researching the case records, the King family produced a documentary entitled Decades of Deceit, which condemns the police and prosecutors for alleged shoddy investigations and uncooperative communication, and, in particular, of disregarding leads the family discovered in 2006. Funds generated from the sale of the documentary were donated to the Tim King fund, designated to help abused children and support activities for Birmingham children.

Forensic DNA tests conducted in 2012 showed that hair found on the seat of Sloan's car and on the bodies of Stebbins and King were a match and came from the same unknown man. The hair DNA does not match Sloan, but implicates someone he knew or lent his car to.

In 2013, an anonymous informant reported a blue AMC Gremlin buried in a farm field now being developed in Grand Blanc. Police are investigating the Gremlin for ties to the crime as King was last seen in a blue Gremlin.