A piece of paper fell from the counter at Haven Drugs in Medford, landing near Raymond Ferguson's body -- helping to point investigators to the dead man's alleged murderer.
Suffolk police matched two fingerprints found on the paper to other prints that belonged to David Laffer, 33, the Medford man charged in the murders of four people Sunday morning at the pharmacy, authorities said.
By midday Monday, a source familiar with the investigation said, police were focusing hard on Laffer. Along with more than 400 tips provided to the police department's CrimeStoppers hotline, a solid lead from the Suffolk County district attorney's office, and other information, Laffer was the focus of the homicide squad's investigation by Monday night, the source said.
But it began with the slip of paper.
"There was a piece of paper that was attached to the counter. . . . That piece of paper became dislodged during the robbery and was found on the floor in the vicinity of Mr. Ferguson," said John Collins, Suffolk's chief trial prosecutor. He spoke down a hallway from the Central Islip courtroom where Laffer was arraigned Thursday on four counts of first-degree murder.
"It contained two fingerprints that have been matched to Mr. Laffer," Collins said.
"Despite the defendant's best efforts to wipe the prints from the scene," Collins said, he missed the piece of paper.
Investigators also learned Monday that Laffer owned a .45-caliber pistol consistent with the one used to commit the murders. They located it, Collins said -- disassembled -- as they executed a search warrant at his Pitchpine Place home in Medford on Wednesday morning.
In addition, spent bullets from the crime scene were traced to Laffer through ballistics tests, sources said. One source with knowledge of the police investigation said the tests "made a connection" to Laffer's 1999 gun permit filed with Suffolk police.
A video camera at the drugstore provided horrific images of the four people being killed. Those images of the killer in Monday's newspapers provided still more leads pointing directly to Laffer, police said.
And help came from New York City's Office of the Special Narcotics Prosecutor, which prosecutes major drug trafficking in the city.
That office passed along information about Laffer to the Drug Enforcement Administration's Suffolk office on Monday, sources said. That was then passed on to the police department. They identified Laffer as a large purchaser of narcotics in the Medford area, including at Haven Drugs.
On Wednesday morning on Pitchpine Place, it all came together.
With Anthony M. DeStefano, Robert E. Kessler and