The missing Connecticut mum's remains still haven't been found, but her estranged husband, Fotis, was charged with killing her.
The blood on her Range Rover was the first clue that Jennifer Dulos' disappearance last May would turn into something sinister.
The weeks that followed brought more revelations from the police, adding to a mystery that gripped the public.
Her blood was also discovered on the seat of a car her estranged husband had borrowed on the day she vanished. Nearly two dozen items with her DNA were found in garbage cans some 120km from her suburban Connecticut home. Then there was her ongoing acrimonious divorce case, in which Dulos, a mother of five, had said she worried she was in danger.
Yet even as each new detail made it more likely that Dulos had met a violent end, investigators could not find one key piece of evidence: her body.
Still, last week, nearly eight months after Dulos went missing, prosecutors accused her estranged husband, Fotis, of murdering her.
In the warrant charging Fotis Dulos, 52, with murder and kidnapping, officials detailed their meticulous investigation. They drew on blood-spatter analysis and DNA evidence to conclude that Jennifer Dulos was fatally attacked. Then, using phone records, surveillance footage and interviews, they built their case for Fotis Dulos' alleged involvement, piecing together his every move.
The laborious process followed a script that prosecutors often have to execute in murder cases where the most crucial piece of evidence — the victim's body — cannot be found.
"At the end, your puzzle is going to be missing pieces," said Tad DiBiase, a former federal prosecutor who wrote a book on homicide cases involving bodies that have not been recovered. "So you need to have enough of the other pieces that you can still see the entire puzzle."
Murder charges brought without a body are relatively rare. These cases require a voluminous cache of circumstantial evidence both to establish the involvement of the accused and to show that the victim was definitively killed.
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But the extra burden might actually make convictions more likely.
DiBiase has tracked just 526 such cases that have gone to trial in the United States since the early 19th century. Of them, 86 per cent resulted in a conviction, he said.
Nationally, the conviction rate for all murder cases is 70 per cent, according to the federal Bureau of Justice Statistics.
"Only the very best no-body murder cases go to trial," DiBiase said.
The Connecticut State Police declined to comment on the Dulos investigation, citing a gag order issued in the case. The state prosecutor in charge of the case did not respond to requests for comment.
One law enforcement official familiar with the case said investigators had gathered far more evidence than they have disclosed.
The charges brought against Fotis Dulos and two others accused of conspiracy to commit murder, Michelle C. Troconis, 45, Fotis Dulos' girlfriend, and Kent D. Mawhinney, 54, a friend, were based on more than what was disclosed in the warrants, the official said.
The investigation into Jennifer Dulos' disappearance began May 24, when her nanny and a close friend called the police after they became concerned she might be missing, according to warrants.
The nanny, Lauren Almeida, told officers that she had reasons to suspect foul play. When she went to Jennifer Dulos' home that afternoon in New Canaan, Connecticut, she found Dulos' handbag, even though she was not home.
Inside the house, Almeida also went looking for paper towels after cleaning a mug of tea Jennifer Dulos had left. When she went to fetch more in the pantry, she found only two rolls despite having placed a twelve-pack there the night before, she told the police.
Her worry grew after multiple text messages to Jennifer Dulos went unanswered and a phone call went straight to voicemail.
"In the almost seven years that I have worked for Jennifer, I never ever had a hard time reaching her," Almeida told the police, according to a warrant.
When the police arrived that same night, they found blood on Jennifer Dulos' Range Rover and in her garage. A second car belonging to her was found abandoned next to a 300-acre park about 5km from her home.
Detectives ultimately determined the blood belonged to Jennifer Dulos, according to arrest warrants. They later found her blood mixed with Fotis Dulos' DNA on a faucet and Fotis Dulos' DNA on a doorknob inside her home, as well as evidence of an attempt to clean up the scene.
Investigators' suspicions turned quickly to Fotis Dulos. At the time of his wife's disappearance, the two had been locked in a bitter custody battle for nearly two years.
When Jennifer Dulos filed for divorce in June 2017, she said she worried her husband might harm her. As the case continued, she said he displayed "irrational, unsafe, bullying, threatening and controlling behavior.'' Fotis Dulos called the accusations baseless.
Detectives used cellphone records to determine that Fotis Dulos and Troconis, who lived together in Farmington, Connecticut, were in Hartford on the night Jennifer Dulos went missing. Surveillance footage showed them dumping trash bags along a miles-long stretch, according to warrants.
When the police checked the trash cans, they found several bloodstained items with Jennifer Dulos' DNA, including her clothing, paper towels and a number of cleaning supplies. At least one black garbage bag had traces of Fotis Dulos and Troconis' DNA.
The police also found four zip ties with Jennifer Dulos' DNA, two of which were stained with her blood, that they said Fotis Dulos had used to restrain her .
On June 1, the police arrested Fotis Dulos and Troconis, charging them with hindering the prosecution and tampering with evidence. Another evidence tampering charge came in September. Both have pleaded not guilty to those charges.
After the first arrest, Troconis began meeting with investigators. Over three interviews, she gave the police conflicting and contradictory statements, sometimes within the same conversation.
The police had found handwritten notes — which detectives called "alibi scripts" — at Fotis Dulos' home that purported to show his and Troconis' whereabouts and activities on May 24.
On June 2, Troconis told the police that she and Fotis Dulos had woken up together on the morning of the apparent murder, then showered and "were intimate together," according to warrants.
Evidence showed that not to be the case, and in later interviews, Troconis admitted the alibi scripts were false. By August, she had told the police that she could not account for Fotis Dulos' whereabouts on the morning of Jennifer Dulos' disappearance.
Mawhinney, the third person charged in the case, was also accused of helping provide Fotis Dulos with a possible alibi.
The alibi scripts mentioned that Mawhinney had visited Fotis Dulos, and Troconis confirmed he was at the couple's home that day for a previously arranged meeting. Though Mawhinney initially denied having a meeting there, cellphone records placed him at the home, according to court documents.
Detectives said they used surveillance footage to track Fotis Dulos from his home in Farmington to Jennifer Dulos' home, about 120km away, on May 24, according to court documents.
The police said that they believed Fotis Dulos borrowed a red Toyota truck that night that his employee, Pawel Gumienny, had previously parked outside Fotis Dulos' home.
Using traffic camera footage, the police traced the truck along state roads to New Canaan. Cameras on school buses showed it parked just 30m from the spot where Dulos' car was later discovered.
Investigators believed that Fotis Dulos then travelled the 5km to Jennifer Dulos' home on a distinctive French-made bicycle that Gumienny told them about, warrants said. Footage later showed a man in dark clothing riding a similar bicycle in New Canaan.
The police believe that Fotis Dulos was lying in wait at his wife's home, where he attacked her and attempted to clean the crime scene between 8:05am and 10:25am, a warrant said.
He then drove Jennifer Dulos' body away in her own car before driving the borrowed red truck back to Farmington, the warrant said.
Days later, Gumienny told detectives, Fotis Dulos took the red truck to be washed and detailed, which both surveillance footage and Troconis later confirmed.
Gumienny also said that Fotis Dulos insisted repeatedly that the seats in his truck needed to be replaced.
Gumienny eventually swapped the seats. But he had become suspicious of Fotis Dulos' persistence, said his lawyer, Lindy Urso, so he held on to the original seats and eventually gave them to investigators.
"It was one of the best decisions of his entire life," Urso said.
The police later found Jennifer Dulos' blood on one of seats.
Fotis Dulos has repeatedly denied any involvement in Jennifer Dulos' disappearance, and has told investigators that he believed his wife was still alive.
"We defy the state to prove that she is in fact dead," one of Fotis Dulos' lawyers, Norm Pattis, said last week.
Throughout their investigation, law-enforcement agencies conducted vast searches for Jennifer Dulos. They dispatched helicopters and drones over a park, sent cadaver dogs to a trash plant and unearthed a potential grave site they linked to Mawhinney.
Every time, they came up empty.
In August, the police presented a summary of their collected evidence, including blood-spatter analysis, multiple blood stains and the items found in Hartford to Connecticut's chief medical examiner, Dr. James R. Gill.
Gill determined that Jennifer Dulos had sustained an injury or injuries that would have been "'non-survivable' without medical intervention," according to the warrant.
He categorised her death as a homicide.
Written by: Michael Gold
Photographs by: Jessica Hill and Gregg Vigliotti
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