'The Skeleton Crew' author Deborah Halber explains how ordinary citizens are helping solve murders

The murdered man with no name was missing more than his identity.

Some of his remains had been found in a bucket of hardened concrete at a Missouri truck stop in 2001, but most of his body was gone. Without fingerprints to rely on, authorities turned to a forensic anthropologist who used both art and science to create a bust of the man's head.

No one recognized it.

Then an armchair detective used the Internet to match the bust to a missing person from a nearby state. And that's not all. The sleuth's online prowess ultimately allowed the man's children to finally lay their beloved father to rest, and her work helped convict the killer.

This case is far from an isolated incident. Missing-person cases are getting an extraordinary amount of attention thanks to American sleuths who identify nameless John and Jane Does from the comfort of their living rooms and basements. The online Doe Network, devoted to missing persons and unidentified bodies, has contributed to the solving of dozens of cases.

As a result, relatives and friends are learning the truth about their loved ones who vanished and are even seeing justice done.

Massachusetts journalist Deborah Halber tells the stories of these remarkable achievements in her fascinating new book The Skeleton Crew: How Amateur Sleuths Are Solving America's Coldest Cases.

In an interview, Halber talks about the motives of these unpaid detectives, the broken system that's left so many missing persons unfound, and the kindness of those who devote themselves to solving mysteries. "I've been really blown away," she says, "by the power of the compassion of strangers."

Q: One of the most dramatic cases in your book is the story of the man whose head was encased in concrete. How did an amateur sleuth ultimately solve that case?

Law enforcement posted a photo of the bust to the online Doe Network, which was been created in the late 1990s by people who wanted to gather all the cases of unidentified bodies in one place. It's accessible to anyone who might want to input information or try to make a match between missing people and unidentified remains.

An amateur sleuth named Ellen Leach came across this bust online. She likes to adopt the most challenging cases and she took this one on as her own, putting forward a lot of potential matches over the years. One of them that she came across was a really good possibility, a picture that had been posted of a man missing from Iowa.

This man [was] named Greg May. He was a big Civil War buff and he had a pretty valuable memorabilia collection with sabers, guns, and so forth. He just disappeared, and his kids got really worried, and eventually law enforcement in Iowa decided he'd been murdered.

She proposed this match, and proposed it yet again, and it made its way to a police lieutenant in Missouri who'd been looking for matches. Within days, Greg May's dentist confirmed that that was his head.

Q: The remains were identified just in time as his killer was on trial in a rare "no-body" murder case, correct?

This demonstrates all the aspects of the process that are so agonizing and so amazing at the same time: The length of time it took with all the twists and turns in terms.

Leach was persistent in trying to find someone to solve this case and it all came together just as the murder trial was in progress. They were able to get the conviction.

Q: None of these sleuths are getting paid. What's their motivation to volunteer so much of their time to the tedious task of poring over photos of missing people and details about unidentified remains?

Sometimes they come at it through these iconic cases that get a lot of press and other times they come across the missing-person sites because someone they know has a missing person in their family and they're trying to help out.

What draws them is the mystery, the challenge. Nobody can really resist a mystery.

Q: What are these people like?

They may not have an extensive formal education, but they're all really smart and really detail-oriented and some of them have powerful visual memory. They all have the ability to stick with it, even though it involves looking at disturbing images in a lot of these websites, which are a kind of Facebook for the dead.

They're also eventually driven by compassion, a feeling that they'd like to provide closure for these families of missing people. They realize these people are someone's daughter or wife or husband or uncle and they feel strongly that they'd like to end that agony for them.

Q: On television and in mystery novels, amateur detectives are always snooping around where they shouldn't be. Do these sleuths ever try to solve cases in person?

I only spoke to a couple people who actually wanted to be out and about knocking doors. For the most part, these organizations discourage people from going out and putting themselves in potentially dangerous situations.

Q: How did the United States end up with tens of thousands of unidentified bodies in the first place?

Partly it was just a sad case of national neglect, something that was not a priority. Law enforcement is overworked and understaffed and they have to jump on the latest demands. These unidentified bodies were just lying there quietly, and often no one seemed to be looking for them.

The other difficulty is that there was a lot of confusion about a national database coupled with law enforcement's reluctance to share information across jurisdictions or share it with the public. It's not something they're typically eager to do and that led to this backlog.

Still, I did come across many jurisdictions where there were detectives who were very committed. Some swore never to retire until their cases were resolved.

Q: What about the other end of the spectrum, police detectives who didn't appreciate hearing from some random person from the Internet?

There were a lot of people getting hung up on and ignored. And web sleuths had shown up law enforcement when some of these cases started being solved and that didn't go over well.

Q: What does it mean for the families of missing people when these cases are solved?

The family of Greg May had put forward a reward and Ellen Leach got that reward money. That family was eternally grateful to recover just a fraction of their father's body – they still send her Christmas cards – and they were grateful that they were able to get the murder conviction.

Q: What have you learned while writing this book?

A lot of these missing people are dependent on the kindness of strangers: The rare detective who adopts them or the medical examiners who don't want to let it go or these web sleuths who keep plugging away even though they have no personal stake.

I've been really blown away by the power of the compassion of strangers.

Randy Dotinga is a Monitor contributor.