Freddie Clyde Tiller Jr. was born on August 17, 1957, in East St. Louis, Illinois. Prior to the murders, Tiller had a criminal history that included theft, shoplifting, armed robberies, and burglary. At the time of the 1979 murders, he was on parole after serving a sentence for armed robbery. 

On April 30, 1979, Tiller, along with accomplice Andre Vernell Jones, participated in a deadly crime spree in East St. Louis, Illinois. Their actions resulted in the deaths of three individuals: Richard Stoltz, a 63-year-old World War II veteran; Samuel Nersesian, a 23-year-old dry cleaning store proprietor; and Debra Brown, a 22-year-old mail carrier. Tiller directly shot Stoltz during a robbery and was present during the murders of Nersesian and Brown, which were carried out by Jones. Both men were apprehended on May 4, 1979. ​

In September 1979, Tiller was convicted of two counts of murder and two counts of armed robbery. He was initially sentenced to death; however, his death sentence was later overturned on appeal due to insufficient evidence that he intended for Nersesian or Brown to die. Subsequently, he was resentenced to two consecutive 40-year terms for each murder. ​

Tiller was released from prison on May 3, 2019, but was subsequently reincarcerated for parole violations. He was released once more in 2022. ​As of April 2, 2025, there are no further public records indicating any additional criminal activity or changes in Tiller's legal status.