During the investigation, a local resident, Posteal Laskey Jr. (June 18, 1937 – May 29, 2007[1]), was declared the main suspect in the killings and was arrested on December 9, 1966, for one of the murders for which he was subsequently convicted.

[2][3] The perpetrator chose as victims women between the ages of 31 and 81 living in Cincinnati's various housing complexes, which were inhabited by poor residents of the city.

During the investigation, it was established that the perpetrator was traveling in taxi number 186 belonging to the Yellow Cab Company, which had been reported stolen to the police a few hours before Bowman's murder.

As a result, the city recorded a colossal increase in sales of weapons and door locks, the level of confidence among girls and women dropped sharply, and the Cincinnati Police announced a special operation to capture the perpetrator.

[7] It was also revealed that Laskey had worked as a taxi driver for the Yellow Cab Company from July to December 1962, when all cars used identical ignition keys, and that he drove number 186.

The company management told the police that after his dismissal, Posteal pocketed the ignition key and a number of other items that he was supposed to hand over.

[9] Based on the circumstantial evidence and testimony,[8] in April 1967, Posteal Laskey Jr. was convicted of killing Barbara Bowman and was sentenced to death in the electric chair.

The date of his execution was set for July 8, 1968, but by then, his lawyers had appealed the verdict by citing the fact that the presumption of his innocence was violated when Posteal was vilified by the prosecutor's office and the media as the infamous serial killer, which they had failed to prove in court.

The intense publicity surrounding the case had prevented their client from receiving a fair trial, but the court rejected the appeal by stating that there was no racial or social prejudice in the decision.