I recently published a book, The Kill Jar, about the Oakland County Child Killings, which occurred over a 13-month period from 1976 to 1977 in the Detroit area. I spent approximately 10 years researching the story, which ended up being as much about my own history with violence as it was about the case, allegedly cold these 42 years now. The murders of the four children related to the case remain officially unsolved. The book, however, details the many reasons that sensible people should believe this case was—contrary to the official narrative—at least partly solved during the early investigative stages, the results quashed.

Central to my argument was a cataloging of evidence found on the bodies, which contradicts the ongoing investigative narrative that there was no physical evidence on the children, ages 10 through 12, each of whom was abducted, held in captivity for extended periods, and eventually asphyxiated. Medical examination and autopsy narratives obtained through the Freedom of Information Act reveal that evidence cataloged as early as 1976 and 1977 was substantive enough to solve most major crimes of this type under today’s prosecutorial standards. Blood, semen, saliva, fingerprints, and human hair fragments were retained but quashed.

It would be unfair to claim that 1970s investigative bodies—which obviously lacked our currently technology—could have used much of this evidence to great end. Investigators did not quash evidence because of an inherent understanding of its future value. Lies were told—and leads were buried—because of an interrelated narrative detailed in the book; a story you’ve no doubt heard before, about the corrupting power of moneyed classes, prosecutors covering their rear ends, and cops caught in the middle.

For many years, I spent a lot of time thinking about the evidence left behind on the victims. What else did the killer, or killers, leave behind?

During and after my writing of The Kill Jar, some of this uncovered evidence was DNA tested. A hair fragment found in the vehicle of a known pedophile, currently serving a life sentence for other crimes, was a DNA match to evidence obtained from two of the bodies. Another individual doing time today—a man who was a teenager and molestation victim in the 1970s—was a DNA match to evidence found on a third body. Without confusing the issue, suffice it to say that the evidence now being tested is linking the crimes to multiple perpetrators, and within these links is the story.

For many years, I spent a lot of time thinking about the evidence left behind on the victims: blood on the shirt and torn underpants, saliva inside the jeans, fingerprints and human hairs on the exterior of a winter coat, and the semen—which nobody really wants to think about. What else did the killer, or killers, leave behind? Which living suspects could be fingerprinted today for comparison to yesterday’s crimes? Whose incarcerated inner cheek could be scraped with a cotton swab for DNA extraction? During the decade of my investigation and writing of The Kill Jar, my focus was often narrow, homing in on those bits and pieces the perpetrator(s) left behind.

Recent technology has evolved to the point that a bullet casing scrubbed with soap and water, leaving no residual fingerprint capable of being isolated by traditional dusting, can still reveal a shooter’s identity in some cases. The shooter’s fingertip moisture can act as a corrosive to the metal casing, so with certain metals and conditions, the individual essentially acid-brands each fingerprint while loading the bullets. These prints, previously written off as nonexistent in the case of a wiped-down surface, remain ripe for extraction. The cold case implications are momentous, as old evidence bags full of metal handguns, clips, and casings get a second look.

There are several new advances in fingerprint technology worth noting in greater detail, but VMD technology (short for Vacuum Metal Deposition)is especially interesting in that it essentially pulls prints from metals via a process of heating other, newly introduced metal fragments to a vapor and allowing them to adhere to the print as a means of highlighting it.

This may be minor for the Oakland County Child Killer hunt. After all, these four kids were murdered by asphyxiation. What I’ve been hunting, however, is the perpetrator’s trace evidence left on the victim—that fingerprint. What if, though, I consider the opposite: What about the evidence the victims left behind? The fingerprints these children imposed upon the metal surfaces during their captivity, the handles or runners of the vehicles used to abduct them, or the bric-a-brac of a suspect’s residence? If prints on a bullet casing can remain for decades, then prints on the remaining personal objects of a victim can be lifted and compared to the personal objects confiscated from a suspect.

We are all made of moisture and skin cells and blood, of tissue and ligaments and cartilage and bone, and of other organic matter that one does not have to be a scientist to understand. If you touch a thing, that thing has been imprinted with a memory of the moment. As the fortune cookie says, “A part of us remains wherever we have been.”

I have been searching through those parts that a perpetrator left behind, each victim of the Oakland County Child Killings a vessel for the memory of those moments besmudged by violence of a cellular level. Today, I wonder, within those visitations, what did the victims leave behind on their perp?