District of Columbia police threw a party yesterday to celebrate the successful end of their year-long effort to raise more than $500,000 to buy bulletproof vests.

"Cynicism is a professional hazard for law enforcement officials," said Gary Hankins, an official of the Fraternal Order of Police, which footed the $1,500 bill for yesterday's thank-you affair. "When we started this a year ago, many police officers were skeptical the community would respond. That cynicism has certainly melted. This proves to us how much the community supports us."

Organizers say that more than 14,000 people, churches, civic associations and corporations have contributed to the vest fund, and all 3,200 police officers on street duty are scheduled to have their $180 vests by Oct. 1.

Several hundred people, fewer than police had hoped for, stopped by the four-hour event. They attributed this to the heat. Many of those who were at the celebration, held at a park near 17th Street and Constitution Avenue NW, were tourists and bicyclists drawn to the area by the music of a six-piece police band and the lure of free snow cones. There were also free fingerprinting demonstrations, video games, balloons printed with "The Police Thank You," and a clown.

Others said they attended because they believed in what the police were doing.

"It really is a beautiful thing they are doing for the kids today," said Florence Pendleton, who took her three children to the celebration. Pendleton said that five police officers belong to her church, Bethesda Baptist Church, which she said raised almost $600 for vests.

Police began the fund-raising drive last fall, after Officer Donald G. Luning was fatally shot by a man he was pursuing. Originally the city denied funds, but later agreed to contribute $250,000 if fund organizers could raise at least that much.

Alan Harper, secretary of the vest fund committee, said a total of $592,000 has been raised, including the city money.

Harper said the District fund-raising effort followed in the footsteps of police in other major cities, who all had to raise money to outfit their officers in bulletproof vests.