UPDATE: Suspect in the Long Island Serial Case Arrested, Charged With 3 Counts of Murder

Like Shannan, the young women discovered in December 2010 were escorts who had advertised their services on Craigslist and Backpage.com. They were in their 20s, petite, and willing to go on “outcalls” to meet clients. 

Maureen Brainard-Barnes went missing in July 2007. Melissa Barthelemy was last seen in July 2009. Megan Waterman disappeared in June 2010. Amber Lynn Costello left for a “date” in September 2010 and never came home. 

The police, still looking for Shannan, continued to comb through the marshes and thick bramble alongside Ocean Parkway. By April 2011, they had discovered six more sets of remains: Four women, the toddler daughter of one of the women, and an Asian man dressed in women’s clothing. 

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Two sets of remains were eventually connected to female torsos that had been discovered years prior in the woods near Manorville, a town 45 miles east of Gilgo Beach. Another was linked to a pair of severed legs that had been found in a garbage bag on Fire Island in 1996. 

Ten bodies. Ten mysterious, violent deaths. Evidence linking each of the nine adult victims—five identified, four unkown—to the sex trade. It was a nightmare come true. A serial killer—or killers—had been using the remote barrier islands off the South Shore of Long Island as his dumping grounds.

But police still didn’t know what happened to Shannan. 

In the end, she wasn’t far from where she’d last been seen. On December 6, 2011—19 agonizing months after she called 911—police discovered Shannan’s purse, jeans, shoes, and cell phone in a swamp on the eastern edge of Orchard Beach. A week later and a quarter mile deeper into the marsh, they found her. 

In perhaps the most bizarre development in a case full of them, Suffolk County detectives quickly determined that Shannan’s death wasn’t connected to the other ten. 

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Their theory, supported by the testimony of the two men whose voices can be heard on the 911 call—Michael Pak, her bodyguard and driver, and Joseph Brewer, the client who paid her to come to Orchard Beach—was that Shannan had been suffering from a bipolar episode or in a drug-induced panic when she ran through the neighborhood screaming for help. Disoriented, she entered the swamp and stumbled through it for more than half a mile before she collapsed and drowned, or died of exposure. “Death by misadventure,” the police called it. 

In the definitive book about the early years of the investigation, Lost Girls: An Unsolved American Mystery, journalist Robert Kolker notes that th e official explanation of Shannan’s death “was practically Victorian in its view of prostitutes, as if [she] had died of sorrow, or fright, or sadness, or heartache. Police seemed to be saying that Shannan Gilbert had died because her soul had been rent asunder by a life in the streets.”  

Shannan’s mother, for one, wasn’t buying it. And she had reason not to. Two days after Shannan disappeared, Mari Gilbert received a phone call from a man who identified himself as Dr. Peter Hackett. The former surgeon with the Suffolk County police department said that he lived in Orchard Beach, where he “ran a home for wayward girls.” Shannan, he claimed, was recovering under his care. 

Three days later, Mari heard from Hackett again. This time, however, he said that not only had he never had any contact with Shannan, he’d never called Mari in the first place. Phone records proved the latter claim to be untrue, and when Shannan’s body was eventually recovered, Mari became convinced that Hackett was somehow involved—his property led directly to the swamp where her daughter was found. 

Related: Gary Ridgway: The Green River Killer Who Evaded Capture for 20 Years

But his former colleagues at the police department were equally certain that Hackett had nothing to do with Shannan’s death or any of the others. His wife and children were home with him on the night Shannan went missing, and, besides, he had a history of making false claims about his involvement in police matters and other newsworthy events. 

Michael Pak and Joseph Brewer were also cleared of wrongdoing. Their accounts of Shannan’s disappearance fit the official version of events, and neither could be connected to any of the other victims. 

Suffolk County detectives were back to square one. 

So they put Shannan’s death in a box labelled “Cruel Twists of Fate” and turned their attention to the four women found in December 2010. The “Gilgo Four,” as they came to be known. 

These women had names. Boyfriends who were with them in the days and nights before they disappeared. Clients who found their ads on Craigslist and Backpage.com. Families who filed missing persons reports when they never came home. 

Related: 7 True Crime Authors Who Became Part of the Story

But the women had secrets, too. Melissa Barthelemy refused to let her on-again, off-again boyfriend drive her to Long Island the night she disappeared. Amber Lynn Costello’s roommate, Dave Schaller, knew that she spoke to the same man “three or four times” on the night she went missing, and that she finally agreed to meet him for $1,500, a much higher amount than usual. But Dave didn’t know the man’s name, or where he lived. 

And not all missing persons reports are treated the same way. A child disappears from the bus stop? It’s national news. A prostitute doesn’t come home the morning after a date? Nobody cares. 

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The fact is, investigators didn’t put much effort into finding Maureen, Melissa, Megan, and Amber when they were first reported missing. They were sex workers and drug users, women who willingly put their lives at risk for a few hundred dollars. It wasn’t until they were found buried in the sand at Gilgo Beach that anybody thought to look for connections between them, or conduct extensive interviews with their friends and acquaintances, or carefully examine their phone and Internet records. By then, the trail had gone cold. 

The most tantalizing piece of evidence was a series of phone calls made to Melissa Barthelemy’s sister, Amanda, in the weeks after her disappearance. Seven calls made from Melissa’s own cell phone, each lasting less than three minutes. The same voice every time—a man’s voice, described by Melissa’s mother as “calm and bland”—taunting a teenage girl about her big sister’s lifestyle. 
“Do you think you’ll ever speak to her again?” the man asked Amanda in his final call. A few seconds later, he answered his own question: He told Amanda that he’d killed Melissa after having sex with her. Then he hung up. 

The calls were made from busy locations near midtown Manhattan and Massapeaqua, New York. On more than one occasion, police pinpointed the cell phone’s signal and used surveillance cameras to try to identify the caller. But it was fruitless—the locations were too crowded, too full of people on cell phones. 

Related: 10 Serial Killers Who Were Never Caught 

The caller seemed to be taunting not just Amanda, but police as well. If he was indeed the killer, his awareness of criminal investigative techniques matched certain clues about the murders. Like the fact that on the nights they disappeared, each of the Gilgo Four received calls from untraceable “burner” phones. And that some of the women had left their own cell phones behind when they went to meet their dates, as if they were doing so at someone’s request. Investigators even surmised that the location of the dumping site, which straddles Suffolk and Nassau counties, might have been chosen to exploit the rivalries and miscommunications that often occur between police departments. 

But there wasn’t much else to go on. Only six of the ten sets of remains were positively identified. The bodies were in various states of decomposition, making it difficult to pinpoint time and manner of death. DNA evidence appeared to be scarce or nonexistent. Police initially suspected that multiple killers had used the GIlgo Beach area as a dumping ground, before concluding that all ten corpses were likely the work of one man—a sophisticated and elusive serial murderer whose methods evolved over a fifteen-year period. 

Detectives wouldn’t say it on the record, but they were beginning to suspect that they were hunting one of their own. A cop or ex-cop, someone with extensive knowledge of law enforcement techniques. A frightening possibility, although it helped to explain how he went undetected for so long. And why he stopped when Shannan Gilbert called 911.

Or did he?

It’s been nine years since Shannan Gilbert’s desperate night in Ocean Beach led to the discovery that a serial killer was terrorizing Long Island. After the initial media frenzy died down, Suffolk County police went silent. They told reporters and family members that the matter was “still under investigation,” but refused to say more.

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In the absence of official developments, amateur sleuths set out to solve the case. They pored over autopsy reports, phone records, police statements, psychological reports, and maps, and posted comments on sites such as Websleuths.com and Reddit. In some cases, their theories were so detailed and convincing that they informed the work of investigative journalists such as Joshua Zeman and Rachel Mills, whose A&E documentary series “The Killing Season” is a must-watch for anyone interested in the case. Other noteworthy reporting on LISK has been done by 48 Hours, People Magazine Investigates, Rolling Stone, and Vice. 

In recent years, a few tantalizing clues have emerged. The first involves disgraced former Suffolk County police chief James Burke, who led the department from 2011 until 2015, when he was arrested for beating a robbery suspect and interfering with the ensuing investigation. Burke had long been rumored to have blocked FBI efforts to aid in the LISK investigation, and shortly before he went to prison in 2016, an online escort came forward to claim that she’d had “rough sex” with the police chief at two cocaine-fuelled parties held in an Oak Beach house in 2011. 

The FBI continues to investigate the tangled web of corruption that surrounded Burke at the Suffolk County police department. Could it lead back to LISK? Or to the truth about Shannan’s death?

The other, even more promising, avenue of investigation points in the direction of a Long Island man who is already serving two consecutive 25-years-to-life sentences for murder. In 2014, John Biltroff, a carpenter and married father of two, was linked by DNA to Rita Tangredi and Colleen McNammee, two sex workers whose bodies were found in Suffolk County in 1993 and 1994, respectively. Biltroff lived near Manorville, New York, a few miles from the spot where the torsos of two women found near Ocean Parkway in 2011 were initially discovered years prior. Biltroff’s lawyer has denied that his client is LISK, but Suffolk County prosecutor Robert Biancavilla said in 2017 that Biltroff was a suspect in at least one of the murders. 

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The police have neither confirmed nor denied Biancavilla’s statement, but reporters and amateur sleuths have helped to fill in some of the gaps. In 2017, Melissa Barthelemy’s mother said that her daughter “had a lot of calls to Manorville from her phone” in the period before her she went missing. And in what could be either an eerie coincidence or circumstantial proof that Biltroff, an avid hunter, stalked his victims and has a higher body count than is currently known, Melissa’s best friend at the time of her death was Rita Tangredi’s grown daughter.

In some ways, it feels as if the solution to the case of the Long Island Serial Killer is close at hand. The breakthrough in the Golden State Killer investigation, which relied on the latest DNA matching technologies, has given hope to cold case detectives all over America. After the Suffolk County police cleaned house in the wake of James Burke’s arrest, the FBI officially joined the LISK investigation, bringing new resources and the most advanced profiling techniques to bear. No one in the public knows how much evidence they’ve gathered at this point, how close they are to declaring the case closed. 

Related: 26 Serial Killer Movies Based on Real Life (and Death) 

Viewed from another angle, however, the mystery is more baffling than ever. Why, for instance, are law enforcement officials still refusing to release the tape of Shannan Gilbert’s 911 call? If her death was indeed accidental and isn’t part of the larger LISK investigation, what are detectives trying to hide? 

And what to make of the recent independent autopsy, paid for the Gilbert family, which concludes that Shannan didn’t drown, but was likely strangled to death? Is it a red herring, or proof that her death and the LISK murders are connected after all? 

[update] In January 2020, investigators shared a "previously undisclosed piece of evidence" in hopes of revealing new leads in the long-dormant case. The photographic evidence depicts a black leather belt found at one of the crime scenes. Embossed on the belt are the letters WH or HM, depending on the viewing angle. 

Suffolk County Police Commissioner Geraldine Hart declined to say just where investigators recovered the belt, which one of the victims it was linked to, or even the belt's size. She did clarify, however, that investigators believed the belt was "handled by the suspect" and that it did not belong to any of the victims. 

Could this be the clue that finally breaks the case? Only one thing’s for certain: Someone, perhaps more than one person, spent fifteen years killing people and dumping their bodies on a remote stretch of the Long Island coastline. When the killer, or killers, is finally identified, ten families—and maybe more—will finally have answers. But they’ll never have their loved ones back. 

Featured photo: Wikipedia and Steveen Manon / Flickr (CC)