This story originally aired March 3, 2007. It was updated Sept. 6, 2007.
When several family members didn't show up for a birthday party in December, 1997, Phil and Nicoletta Dosso drove to their business to see where everyone was.
As correspondent Harold Dow reports, what they found inside was beyond their comprehension: three of the family members and their long-time friend and partner were all shot execution style. With no forensic evidence, the case would be hard to crack and authorities recruited one very tenacious cop to tackle the case.
Would he be able to track down the killer?
Dec. 3rd was always a special day for Maria Dosso and her husband Frank - it was the date they started dating and on that date in 1997, it was also the tenth birthday of their twin daughters, Mara and Nicole.
The whole family was going to get together for coffee and cake. "I was expecting Frank to get home at around 5:30. At a quarter to six, he wasn't home yet, and no one answered the phone when I called the factory," Maria remembers.
She decided to call her mother-in-law, Nicoletta.
Frank worked for his father, Phil, an Italian immigrant who was co-owner of a thriving manufacturing plant in Bartow, Fla.
Nicoletta and Phil's daughter, Diane Patisso, a young state prosecutor, was supposed to meet her brother Frank and her husband George at the factory. But she was nowhere to be found.
The Dossos decided to drive to the Erie Manufacturing Company to see what had happened. When she walked in, Nicoletta Dosso was devoured by a world of unimaginable horror.
"Diane was on the floor. Oh my God. It was so bad. It was so bad. And I said 'Maybe she's alive. Maybe she's alive,' but she wasn't. She wasn't," she remembers. "And then I said 'Let me go see. Maybe Frankie is…something happened to them, too.'"
Phil Dosso rushed in after his wife, and was also overcome by the carnage. He frantically called 911.
Shot dead were four of the most beloved people in the Dosso's life: not only their daughter, but also their son, their son-in-law, and George Gonsalves, Phil Dosso's longtime business partner and friend.
Gonsalves was usually alone when he closed up the factory, but on that night fate had placed the three others with him. Who would want to kill these four people, placed together by a quirk of timing?
Police believed there was a single killer, one who was very careful: at the crime scene, no fingerprints, DNA or murder weapon were found.
Within two days, the Florida Department of Law Enforcement dispatched Special Agent Tommy Ray, one of its shrewdest homicide detectives, to hunt for a killer who seemed to have ice in his veins
"George Patisso was shot five times in the back of the head, George Gonsalves was shot twice," says Ray, who tells Dow all four victims were shot execution style. "He then comes over where Frank is trying to get up...and then Frank Dosso was shot three times."
Diane Patisso was the last one to be killed. "He chased her out here in the hallway," Ray explains. "Diane was shot twice in the back of the head."
Amid the bloodshed, there seemed to be signs of a robbery. Desk drawers were pulled open, and papers strewn about. But Ray thought it looked staged and two other things caught his eye: dusty shoe prints left on the seat of an office chair and a ceiling tile that was somewhat raised.
Ray checked out more than a thousand leads; all lead back to one man. "The day of the homicide they initially told the Bartow Police that … Nelson Serrano … you know, 'Look at Nelson Serrano,'" Ray explains.
Nelson Serrano was the third partner, along with Dosso and Gonsalves, in two sister companies, Erie Manufacturing and Garment Conveyor Systems.
The businesses had made the three very wealthy men, but bitter fights with Serrano over money began to tear them apart. Dosso and Gonsalves accused Nelson Serrano of graft, then theft, and eventually forced him out.
When Nelson Serrano returned to the factory, he was furious to discover that George Gonsalves had locked him out.
"George Gonsalves calls the police, 'cause Nelson tries to kick the door in of his former office. Then Nelson, in turn, calls the Bartow Police Department and makes a 911 call as well," Ray explains. "I mean, he hated George Gonsalves worse than anything. And this just kept adding fuel to the fire."
Asked why he thinks the others were killed, Ray says, "They were there. They knew him. You know, he wasn't gonna leave anyone there to testify against him."
But Serrano's family is convinced that he had nothing to do with the murders. Maria Serrano and her son, Francisco, say Nelson Serrano was falsely accused by the victims' families from the very start
"We're extremely sorry for what they went through, but they need to open their eyes and see that accusing my father is not the solution to their grief. And it's taking this tragedy and making it worse," Francisco says.
Francisco Serrano had also worked at the factory and was fired just weeks before his father was ousted. Francisco had been a suspect in the murders until his alibi checked out. Tommy Ray was stunned to learn that his father's did too.
On the day after the murders, Nelson Serrano told officers that he had been in Atlanta - nowhere near the murder scene. There was a hotel receipt and hotel surveillance pictures showing him in the lobby to back-up his story.
It was an alibi caught on tape, proving that on the day of the murders, Nelson Serrano was 500 miles away. But Ray still had his suspicions, and they were only deepened when he called Serrano to talk about the murders.
"He spoke of no remorse," says Ray. Despite that it had been just over a week since the murders; Ray says Serrano launched into a diatribe about George Gonsalves.
Asked if Nelson sounded like a killer, Ray says, "Yes."
But he could he prove it?
Ray was convinced that the truth about Serrano and the Bartow murders was hidden, blotted out by a lie as blinding as the white light of the Florida sun.
"Did you think maybe you got the wrong guy?" Dow asks Ray.
"I thought he had hired someone to do it," the special agent replies.
Suspicion fell on Serrano's 25-year-old nephew, Alvaro Penaherrera. Records showed a flurry of phone calls between the two men around the time of the murders. And one, on the very morning of the murders, was of special interest.
A call was made to a car rental company in Orlando. When he followed up on that call, Ray says he found that there was a car that was rented on the morning of the day of the murders, shortly after the phone call to Nelson Serrano.
A blue 1997 Nissan, which Ray believed Nelson Serrano had asked his nephew to rent. But was the rental car for Alvaro, and was he the hit man?
Ray wasn't sure, but he did have a hunch. And he went back himself to check Serrano's airtight alibi, that critical Atlanta hotel surveillance tape, just one more time.
"Nelson was on the video at 12:20 p.m. on December 3rd, the day of the homicide," Ray says.
Ray patiently waded through hours and hours of tape until, amazingly, he saw Serrano again. "He returned back to the lobby area at 10:17 p.m., so there's like a nine hour and 57 minute gap," he says.
Serrano had told police that he had spent the day with a migraine headache, sleeping in his room.
But if that was true, Ray thought that one thing on the tape seemed very odd: how Serrano was dressed. "He was wearing the same outfit, the jacket, the turtleneck sweater at 12:20 that he was wearing at 10:17 p.m.," Ray explains.
Ray had a theory: somehow, Serrano had used those nine hours and 57 minutes to execute an audacious and brutal crime. "He had time to fly to Orlando, pick up a rental car, drive to Bartow, commit the homicides, and then fly out of Tampa back to Atlanta," he explains.
The theory was far fetched. Ray had no proof that Nelson Serrano had even flown out of Atlanta that day. He knew that Nelson and his nephew Alvaro had been up to something - but what?
Ray put both men under surveillance for a full year.
He knew he had to shake the truth out of Alvaro. When he finally hauled him in for questioning, Ray had a trick up his sleeve: with Alvaro watching, Tommy Ray pulled out a warrant for an old charge against his uncle. "And I said 'Nelson, get up, you're under arrest,'" he remembers.
Alvaro was fooled into thinking his uncle was being arrested for the murders in Bartow. "I saw Nelson getting handcuffed. And it just freaked me out, I mean it totally blew my mind," Alvaro tells Dow.
Alvaro was frightened he'd be next. Asked if they threatened to charge him with murder, Alvaro says, "Basically."
At first, Alvaro insisted that he had rented the car for a friend but Ray wasn't buying it. Eventually, Alvaro caved in. "He got emotional and said, 'My uncle's gonna kill me.' You know, he said - 'I hate to do this, but I rented it for my uncle Nelson Serrano,'" Ray recalls.
He rented the car on the day of the murders, December 3rd. Alvaro said on the very next day, his uncle told him the rental car had been left at the Tampa airport garage, and asked him to return it. He offered to pay off Alvaro's $2,000 credit card debt for the favor.
Despite this new information, Ray still didn't have nearly enough on Serrano. "We didn't have any eyewitnesses," he remembers. "We actually didn't have any way to physically put Nelson in Florida."
There was no way to keep Serrano on a tight leash. That old charge against him had been thrown out and Ray's investigation was stalling.
"I lost faith that time was going on and on and nothing was resolved. So, and he says, 'Mrs. Dosso,' he says, 'I promise you, I will never retire till I do this case,'" Nicoletta remembers.
During a talk with Phil and Nicoletta Dosso, Ray admitted he was growing frustrated. "I'm talking to Mr. Dosso. 'Mr. Dosso, we know Nelson came back.' I said, 'But we cannot come up with a name, how in the world he got back from Atlanta.'"
Ray says if Serrano flew, he didn't do so under his own name or any other names they had on file.
Phil Dosso remembered that Serrano had a son from his first marriage, and Tommy Ray dug up his mother's maiden name: Agacio. Could that be a name that Nelson Serrano would use? The flight manifest gave Ray the stunning answer.
"We have a Juan Agacio that flew out of Atlanta, and the timing would have been perfect," the special agent explains. Ray was certain that Serrano, with forged ID, had stolen a name out of his past: Juan Agacio.
Armed with that information Ray believed he could win an indictment. "I went to the state attorney's office cause I felt it was enough and the state attorney's office said we cannot place him here in Florida and basically that's not enough," he remembers.
Ray knew he still needed even more. He had to establish exactly when the rental car left the garage at the Orlando airport. That would tell him if the car could have reached Bartow a little after 5 p.m., in time for Nelson Serrano to commit the murders.
"I had sent a couple agents over to try and find parking tickets," Ray remembers. "They were told that the tickets had been destroyed. There was no tickets."
But Tommy insisted on searching the parking company's storage area himself, and when he did, he uncovered thousands of forgotten tickets. One was the needle in the haystack - a ticket proving that the rental had left the Orlando airport on Dec. 3rd at 3:49 p.m.
Ray believed that someone could have driven the 80 miles to the murder scene in about an hour and fifteen minutes. But was that someone Nelson Serrano?
At that point, Ray couldn't place Serrano at the airport at that particular point.
The airport parking tickets were rushed to the crime lab in Tampa. And then the proof that Tommy Ray so desperately needed surfaced: Serrano's fingerprints were found on two tickets - one of them was the ticket dated Dec. 3rd, 1997 and that was just the proof he needed.
Serrano was seen on the hotel video at 12:20 p.m. and again at 10:17 p.m.
Four long years after the Bartow homicides, Tommy Ray finally won his indictment against Nelson Serrano. But their battle of wits was hardly over. As it turns out, it had thousands of miles and many years left to go.
Serrano and his wife had returned to their native Ecuador, a country with no extradition treaty with the United States. Now the victims' families wanted to know whether Serrano would ever be held accountable for the murders.
But with Serrano out of reach, Ray was told to put the case on the back burner, and he was re-assigned to another investigation halfway across the state, in Miami.
By sheer luck, Ray was booked at a hotel hosting an international law enforcement conference, and he got a list of officials to look up in Ecuador. Ray urged his bosses to put him back on the Serrano case.
"His bosses say, 'Jesus, it's Tommy. You know him. You know, he might just, he might just pull this off.' 'Give him so more rope, let's see what happens,'" remembers Polk County State Attorney John Aguero.
In Quito, Ecuador, some 2,000 miles and a world away from central Florida, Tommy Ray was determined to arrest Serrano for the brutal murders of four people. And he wasn't about to leave without him.
48 Hours asked Ray to return to Ecuador to retrace his steps. He spent days knocking on doors at one ministry after another. His mission to Ecuador was looking like a fool's errand. Ray was told in no uncertain terms that Nelson Serrano would never be handed over.
He ignored an order from his bosses in Florida to return home, and instead set up shop at the Turtle's Head Pub, a bar for expatriates in downtown Quito.
"I just felt there was some legal loophole or something that we could find to get Nelson back," Ray remembers. It turned out to be a loophole bigger than he ever imagined.
"What he finds out is if he can show that Nelson Serrano is in fact not an Ecuadorian citizen, you might have a hope. Because then you're talking about deportation, not extradition," says Aguero.
It turns out Serrano got into Ecuador using his U.S. passport. When Serrano had obtained U.S. citizenship back in 1971, it had come at a cost - the Ecuadorian constitution had forbidden dual citizenship.
But the information was of little use, unless Serrano could be caught. Ray was told that he was living quietly in an upscale Quito neighborhood.
But Ray didn't have the authority to arrest Serrano himself. According to Ray, the local police were more than happy to help him.
"I was told that we needed about 30 off-duty Ecuador National Police. And could we assist in their off-duty salary?" Ray remembers. The off-duty salary was one dollar an hour.
A small band of off-duty policemen trailed Serrano to a restaurant which was tucked away in a local hotel.
Maria Serrano was having lunch with her husband at the time, as agents confronted them outside. "We see these like 10 guys approaching us. And we thought they were going to rob us. So we keep saying, you know, 'What is going on?' And then they push him against the car. And they start touching his body," she tells Dow.
Maria Serrano says the men were in civilian clothes, and did not present any badge or identification.
Serrano was hauled before a deportation judge in the middle of the night, who ruled that he should be deported immediately.
Serrano's son Francisco says his father is the victim of a kind of vigilante justice. "He wasn't brought back legally at all. My father was completely kidnapped," Francisco claims.
And Francisco tells Dow that at the time his father was in fact a citizen of Ecuador.
Relatives in Quito say that Serrano's Ecuadorian citizenship was reinstated under the country's current constitution, but he was never given a chance to make his case.
"He was not allowed to have an attorney of his own," says Ana Ordonez, Nelson Serrano's niece. "Nelson Serrano was denied his own attorney. He was denied to see or talk to his family."
"So when he says that he was treated unfairly and his constitutional rights were violated, you're saying it didn't happen?" Dow asks Ray.
"It did not happen. He was brought to justice the legal way, and all this other stuff is smoke that he's trying to create," the special agent replies.
Serrano was secured overnight in the K-9 unit at the Quito airport. By early morning, Tommy Ray was waiting for him aboard a plane bound for the United States.
Nelson Serrano was finally headed home to face trial for four counts of first degree murder.
With the approaching trial, the families of the victims know their worst nightmares are about to return. "I'll never be the same. I mean, I put this mask on, but I think of my son every day. Every day I think of my son," says George Patisso. "And it's changed me, it's changed me."
They put every ounce of their faith in Tommy Ray.
It is now 2006 and Nelson Serrano has been sitting in jail for four years since his deportation from Ecuador and his son Francisco is impatient to clear his father's name. "Alright, we're just gonna have to go through this, get it all out in the light. Let the truth be known. And my father will have his freedom back," he says.
Prosecutor John Aguero has his work cut out for him, with no forensic evidence found at the crime scene. His case rests entirely on Tommy Ray's account of the nine hours and 57 minutes in which he says Nelson Serrano carried out his deadly plan.
Defense counsel Cheney Mason knows the state has no hard proof and no smoking gun. "The evidence fails to put him in Bartow. Then it fails to put a gun in his hands. The evidence fails to put him at the scene of the crime," Mason told jurors during the trial.
Mason dismisses Ray's timeline. "I think it's ridiculous," the defense attorney argues. "First he'd have to be able to drive from Orlando International Airport, drive to Bartow, commit the murders and get into Tampa. You're not gonna do it with a helicopter. It's not physically possible."
Serrano's lawyers paint his nephew Alvaro as a liar, who collapsed under Tommy Ray's bullying.
The defense also wants the jury to wonder if Alvaro is in fact the murderer.
"You don't know where you were after 4 p.m. on December 3rd, 1997, do you?" a defense attorney asked.
"No. Not exactly, no," Alvaro responded. He also acknowledges on the stand that he knows how to fire a handgun.
From the start, Tommy Ray's single-minded pursuit of Alvaro's uncle is put to the test.
When asked whether he focused on Serrano from Dec. 5th until his arrest, Ray acknowledges that he had.
Ray's failure to find any evidence in the rental car was also made painfully clear. Questioned by Mason, Ray had to acknowledge that no forensic evidence, like DNA, blood, fingerprints or hair linked the defendant to the crime scene.
The defense claims all of the state's evidence is rife with reasonable doubt:
That raised ceiling tile at the crime scene - an employee testified Serrano had kept a gun in the ceiling. But no murder weapon was ever found.
As for the dusty shoeprints on an office chair, experts couldn't prove they were Serrano's. Did he really stand on the chair to reach for a murder weapon?
A sheet of passport photos found in Serrano's home - two of them were cut out but police never discovered any fake IDs.
And Nelson Serrano's interview with police one day after the murders - he speculates about what might have happened to Diane Patisso.
"One of the statements that he made in there was that Diane Patisso must have walked in the middle of something. In listening to that statement, how would he know unless he was there?" Ray asks.
But does Serrano's speculation really prove a thing?
The state's only piece of concrete evidence consists of two fingerprints on those airport parking tickets, Ray's prize discovery.
"I say it's bogus. To be nice, we will present a theory of how that partial fingerprint miraculously survived all those years and could have been planted on that card," defense attorney Mason tells Dow.
Ray is compelled to vouch for the fingerprints, and for his own honor as well. On the stand, he insists he did nothing to tamper with the tickets and that he handled them with plastic gloves.
But Serrano's lawyer Cheney Mason suggests Ray's discovery is just too good to be true. "Agent Ray miraculously found the card that miraculously has a fingerprint and he's posing for a photographer taking a picture of him finding that card," Mason says.
He says Ray's grandstanding smacks of sheer ambition. "He gets credit for clearing this biggest homicide case in the history of Polk County."
The prosecution rests after calling 60 witnesses
Nelson Serrano doesn't testify in his own defense and his lawyers call no witnesses at all, confident the state has failed to prove its case.
After six weeks of court, the case against Nelson Serrano is in a jury's hands, and out of the hands of Tommy Ray.
Throughout the proceedings, the families of the victims have been under strict judges orders to tightly control their emotions. Nelson Serrano's family is confident, certain that he will soon be a free man.
The jury returned a verdict after only six hours of deliberations: guilty on all four counts of first degree murder.
For the families of the victims, the news is overwhelming. "I'm glad he's not gonna be walking the streets. He's not gonna have much of a life," says Frank Dosso's widow, Maria.
The verdict was also a triumph for Tommy Ray. "I immediately looked over at the family members and saw the relief and the stress that to me was immediately taken off their face and the joy," he remembers.
Frank Dosso's twin daughters are now 19, their birthday, Dec. 3, forever darkened as the day their father was killed.
Nine years of pain and rage echo through the halls. "Now he's going to suffer what he did to my kids," Nicoletta says. "What he did to my kids he took everything away from me."
Nelson Serrano's family files out of the court room grim faced. Both Maria and Francisco Serrano express shock at the verdict.
Asked if he had anything to say to the jurors, Francisco tells Dow, "How could you look at the timeline and say that a man could possibly do this? Do you think this guy's a magician?"
Bitterness toward Nelson Serrano will not be washed away, no matter what his fate.
"His punishment will be in his next life. That's what I feel. I don't care if he's in prison for the rest of his life or if he gets the death penalty," Ann Marie says.
For Tommy Ray, the long pursuit is finally at an end.
Nine months after the verdict and nearly a decade after the murders, the victims' families, Tommy Ray and Nelson Serrano are back in court, this time to hear the judge's final decision: "The court has decided to impose four sentences of death, one for each of the victims. It is the judgment and order of the court that you are sentenced to death by lethal injection … in the custody of the Department of Corrections and you are remanded to the custody of the Sheriff of Polk County for the execution of the sentence."
"Nelson Serrano very clearly thought he was gonna get away with this. I don't think he had any doubts in his mind at all. He absolutely planned this out meticulously and believed that nobody would ever be able to follow this trail," Aguero says.
But somebody did. "He thought he was smarter than you," Dow remarks.
Says Ray, "Yes, Sir, he did."
The death sentences trigger an automatic appeal to the Florida Supreme Court.
Produced Steven Reiner
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