How did he become the focus of the investigation?
Investigators in the Danielle van Dam case are looking for similarities to other abductions over the years, including an unsolved 1974 crime in which a girl was kidnapped and killed three miles from Danielle's home, authorities said yesterday. "At this point, more than 100 items of potential evidence have been gathered from the van Dam home, a neighbor's home and two vehicles belonging to that neighbor," police spokesman Dave Cohen said. Police have not said what caused them to focus on Westerfield. He attracted police interest after he came home Feb. 4 from a weekend trip to the desert. Westerfield said he encountered Danielle's mother at a Poway nightspot the night of Feb. 1 before leaving for the Imperial County dunes in Glamis.
Imperial County dunes scoured for missing girl
http://video.uniontrib.com/news/metro/danielle/20020208-9999_1n8saga.html
February 8, 2002
Tow truck driver says suspect's vehicle was stuck in sand off road Dan Conklin, who owns a tow service that caters to all-terrain vehicles, said he spent more than two hours midafternoon Saturday getting David Westerfield's motor home out of the sand Westerfield,...has said he drove his motor home to the desert Saturday morning, the same day Danielle's parents discovered her missing. Conklin said he found Westerfield, who has been described by friends as an avid desert camper, in an area people do not normally take motor homes.
After the vehicle was freed, Westerfield was in such a hurry, he left behind the motor home's leveling ramps, Conklin said. He "just wanted to get out of there," Conklin said. "He just got on the highway and left." Conklin said San Diego police and agents with the Bureau of Land Management questioned him Tuesday. He took bureau officers to the place where he found the motor home, and they spent several hours there.
"I know this desert well," Conklin said. "This person did some things that were not normal at all."
Westerfield cooperated during several police interviews earlier this week, but Wednesday night his demeanor reportedly changed. One investigator said Westerfield has "clammed up." Yesterday, he retained San Diego defense attorney Steven Feldman. About a dozen undercover officers in unmarked cars were stationed outside Westerfield's home before dawn, then followed him as he drove to Feldman's office in Golden Hill, east of downtown, about 8:30 a.m. He also was trailed by the media, which have converged in Sabre Springs as the case has drawn increasing national attention. Tracking his every move on a police radio, detectives watched Westerfield stop briefly in front of downtown police headquarters, noting that he was making a call from his cell phone. When he drove up Broadway toward Feldman's office, Westerfield stopped again, got out of his Toyota 4Runner and visited with a woman in a white pickup. That prompted detectives to yell, "Get the license number of that truck."
How did he become the focus of the investigation?
Because SOMEONE told the SDPD to look close at him, IMHO!!