Local police said Buddy was accidentally struck Wednesday afternoon on Route 117, a busy two-lane road at the end of Old House Lane, the cul-de-sac that includes the ex-president's home.
"(The former president's) dog was hit by a car ... we received a call yesterday afternoon," said Sgt. Charles Ferry of the New Castle, N.Y., police that also covers suburban Chappaqua in Westchester County north of New York City.
Julia Payne, a Clinton spokeswoman, said neither the ex-president nor his wife, Sen. Hillary Rodham Clinton, was home at the time.
"We are deeply saddened by Buddy's death," the Clintons said in a statement issued by Payne. "He was a loyal companion and brought us much joy. He will truly be missed."
Police said it was unclear whether Buddy was being walked at the time of the accident or had escaped from the Clinton home. He "just darted out in front of a car," said Officer Larry Green. The driver, whose name was not made public, was not at fault, police said.
The Clintons got Buddy as a puppy in late 1997, just weeks before the Monica Lewinsky scandal broke. The dog was named after the president's great-uncle, Henry Oren "Buddy" Grisham, who had died earlier that year.
Spokesman Mike McCurry quipped at the time that Clinton got the dog, a present from a friend, because ""It's the president's desire to have one loyal friend in Washington."
Buddy became one of the most photographed pets in the nation, often seen playing on the White House grass or bounding into a helicopter headed for Camp David.
Clinton acknowledged that the family's senior pet, Socks the cat, was not happy at all with the newcomer. When the Clintons left the White House last year, Socks was adopted by the ex-president's secretary, Betty Currie.
In his first weeks in Chappaqua, Buddy became a signal dog for the reporters who camped outside the home. When Buddy emerged, it often meant the former president was coming out, too.
He once sniffed out a box of reporters' doughnuts and quickly ate three. Another time, when playing fetch with Clinton, Buddy became entangled in the ex-president's legs and knocked him down in full view of the cameras.
"You guys got a good shot," Clinton said. "That's the first time he's knocked me down in all the time we've been together."
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