TAMPA — Scott D. Overbeck, the focus of an investigation into the disappearance of 5-month-old Sabrina Aisenberg, says detectives told him that they found blood in his boat.
They didn't tell him whose blood, he said in a sworn statement last week. Overbeck, who lived in a waterfront home and has owned many boats, didn't think much of the claim.
"Well, all boats got blood in it, I think," he said. "Every boat I ever had does. Somebody either cuts their foot or you catch a fish."
But the boat in question is one Overbeck believes he bought from the baby's mother.
In recent months, Hillsborough sheriff's detectives have been chasing down an informant's contention that Overbeck retrieved a small white boat with the dead baby inside from the Aisenbergs' home in Valrico on Nov. 24, 1997, the day Sabrina was reported missing. The informant said Overbeck then used the boat to dispose of the body in crab traps near the Courtney Campbell Parkway.
If that story proves true, the boat and DNA rumored to have been found on it could prove vital in cracking the decade-old case.
But Barry Cohen, the Aisenbergs' attorney, said his clients never owned a boat, and no neighbors ever saw them with one. State records do not appear to link a boat to the parents.
"That would have been a huge focus of the investigation," he said.
Cohen calls the rumors of DNA "bulls---."
Authorities, Cohen said, "leaked it out there to let someone think they had a good case."
But experts say it is possible for genetic material to exist after all this time — even if the crime scene has been disturbed.
"People still go back and get DNA that's hundreds or thousands of years old," said David Foran, director of the forensic science program at Michigan State University.
The Sheriff's Office has refused to comment on whether it found DNA on Overbeck's boat, citing the continuing investigation.
But it seems pretty certain that the agency has the watercraft.
Overbeck, who talked to Cohen in a jailhouse interview last week, said he unknowingly sold it to an undercover detective last year.
The 12-foot miniature cigarette boat had been sitting in his driveway in Dana Shores with a broken motor. An undercover detective drove up in a white Suburban, he said, and posed as a man looking to buy a boat that would bring back good memories for his dying father.
Overbeck sold it for about $2,200 or $2,300, according to his sworn statement. He thought it was a bit strange that the man hadn't asked for a title. Not that Overbeck had one.
He said he never got a title when he bought the boat for $1,500 some time in the week before Sabrina disappeared. Overbeck said he found the boat in Boat Trader and bought it from a woman in Valrico who told him that her husband was too tall to comfortably ride in it.
As years passed and the mystery went unsolved, Overbeck said he started to wonder aloud to friends about whether his boat might have been linked to the crime. He said the boat had new carpeting when he got it and seemed like it had room enough to hide an infant.
In his sworn statement, Overbeck denied having any personal involvement in the baby's disappearance. Overbeck, a felon, is being held in jail on unrelated federal explosives charges.
The informant, Dennis Byron, said he vaguely recalled that Overbeck and a friend changed the carpet so that there wouldn't be any evidence.
That friend, John Doyle, told the Times that neither he nor Overbeck ever cleaned the boat.
Cleaning a particular area of a crime scene would remove a genetic sample, said David Lazer, a Harvard University professor who has written extensively about the use of DNA in criminal investigations. If carpet had been replaced inside a boat, for example, the DNA may have been tossed out with the old carpet, Lazer said. He said investigators then might look for samples in other areas, such as the walls of the boat. "If it was a location that was relatively safe, sheltered in some sense, DNA can be quite durable," he said.
"This isn't a pristine crime scene," said David Kaye, a professor on science and the law at Arizona State University. "It's going to be more complicated. Certainly it's worth investigating and seeing how much can be found there."
DNA experts say that if a location has been cleaned in an attempt to hide a crime investigators can spray chemicals to identify where they should look for blood to extract DNA.
One such chemical is luminol. When sprayed on even minute amounts of blood, luminol reacts with the iron in the blood and causes the spot to glow neon blue. But luminol only indicates that blood might be in the area. Other substances, such as bleach, react the same way.
When this reaction occurs, investigators swab the area and test the sample in a laboratory to distinguish human DNA from other specimens.
"You couldn't accidentally mistake fish DNA for the baby's," Lazer said. "More importantly, you would need to be able to distinguish the DNA from the crime scene from any other human being."
The ability to do that, he said, would depend upon the quality of the material collected.
"A match does not mean guilty, just as a general proposition," Lazer said. However, he added, "a match combined with other facts can equal guilt."
Times staff writer Rebecca Catalanello and researcher John Martin contributed to this report. Colleen Jenkins can be reached at firstname.lastname@example.org or (813) 226-3337.