The brutal slayings of Hee Wan Yoo, his wife and two children in their Granada Hills home more than two years ago left investigators struggling to solve a crime without suspects, witnesses or motives.
Hoping to generate leads, the Los Angeles City Council offered a $25,000 reward for information that would help solve the slayings. Although the reward was doubled by Yoo family relatives and renewed last month after it expired, it has remained unclaimed. Concrete leads have yet to come in.
But unclaimed rewards are not unique. About 80% of the rewards offered by Los Angeles city and county officials over the past two years expired without being claimed, according to city and county records, begging the question: Why don't rewards work more often?
Despite the low success rate, most law enforcement officials still believe in the concept, saying rewards provide a valuable incentive.
"We often have someone who is wavering about whether they want to share their information, and (rewards) are just an added incentive," said Los Angeles Police Lt. Al Moen, head of the department's major crimes division.
But some police and government officials say privately that rewards are not a reliable crime-fighting tool. Instead, they are seen as a tool of the politicians and a way for the grieving families to feel they are helping to solve the crime.
"Many times it means something to the family," said one homicide investigator. "They feel more is being done if a reward is being offered."
Rewards have been a staple of the American justice system as far back as the 1800s, when posters pinned to saloon doors offered rewards for the capture of train robbers and cattle rustlers--dead or alive.
Today, most rewards are offered by government agencies or relatives of the victims for particularly heinous crimes. Television has gotten into the act with a slew of programs that re-enact crimes and offer rewards for callers with information.
Some reward programs, such as the city of Los Angeles' graffiti reward program, are highly successful. Since 1991, the city's program has paid out $85,500 in rewards to more than 100 people who have helped capture graffiti vandals.
But because such rewards are offered on an ongoing basis, it is difficult to compare their success rate with programs that offer rewards for a particular crime and for a limited time.
In the past 24 months, the Los Angeles City Council paid out 10 rewards, totaling $190,000, according to city records. But during the same period, 63 rewards, totaling $1.5 million, expired without being claimed, records show.
Rewards offered by the County Board of Supervisors do not fare much better. Five rewards, totaling $55,000, have been paid out in the past two years, while 20 rewards, totaling about $206,000, expired without being collected, according to county records.
"For the most part, they are never claimed," said Georgette Dame, a supervisor of the county reward program.
Rewards offered by the city usually expire 60 days after they are offered; county rewards expire after 90 days. But the rewards can be extended or renewed at the request of a county supervisor or City Council member.
Law enforcement officials say there are many explanations for the low collection rate of such rewards. The main reason, they say, may be that witnesses or other sources of information are afraid of reprisals if they call police.
Police say the best sources of information are often accomplices in a crime or friends and family of the criminals--people who have much to lose by providing police with information.
Los Angeles County Sheriff's Lt. Frank Merriman said rewards often do not work because "you are trying to entice the shady person, the associate of the criminal."
Another reason may be that rewards are often only offered for the crimes that are the most difficult to solve, such as murders. According to the most recent FBI statistics, the percentage of homicides solved nationwide dropped from 90% in 1960 to 65% in 1992.
Gary Auer, head of the FBI's office in Ventura County, said no amount of reward will help if no one has information about the crime except for the criminals themselves.
"It can be that a crime is committed by one or two people and they have kept their mouths shut," he said.
Most often, Auer said, law-abiding citizens with information do call police, regardless of whether a reward is offered. He said the FBI gets dozens of tips daily on bank robberies, but "not more than one in 20 asks if there is a reward."
"Generally, we have not seen that rewards have been a significant motivating concern," he said.
Another reason for the low success rate, law enforcement officials say, is that the news of the rewards may never get to the people most likely to have information.