In a sheriff's squad room in Commerce, justice deferred takes the form of office clutter.
Crowding the desks are thick stacks of brown accordion files--notes on open homicide cases, part of a growing trend of unsolved murders.
Each represents a life lost, a family bereaved, a killer gone free.
"They sit at your feet," said Sgt. Delores Scott, a Los Angeles County sheriff's detective. "You are reminded of them on a daily basis."
With gang crime again on the rise in Los Angeles, many law enforcement agencies have seen so-called "clearance" rates plunge below the 50% mark in recent years.
Many factors may be driving the change, which is national in scope. But criminologists say that it's often not the police who are to blame.
Rather, it may be the changing nature of violent crime. Fewer domestic homicides and more gang killings mean murderers are less likely to know their victims. That makes them harder to catch.
The costs are felt in the denial of justice to victims and their families. But also affected are the detectives, who, regardless of their skills, are less and less likely to solve their cases.
In Los Angeles, detectives talk of unsolved murders stacking up over the course of a career. Even if you just have four unsolved cases per year, "you're here 10 years, and that's 40 unsolved cases," said Capt. Frank Merriman, a veteran homicide detective for the Los Angeles County Sheriff's Department.
Such cases gnaw at the imagination, weigh on the conscience.
And they quite literally hang over investigators' heads.
At the Los Angeles Police Department's North Hollywood Division, the mere mention of unsolved murders prompts Det. Mike Coffey to glance upward.
Five unsolved gang slayings this year are listed in felt-tip pen on a board over his desk. He likes to keep the names in plain view, he said.
"We have two or three mothers who call every anniversary of the death of their children," he said. "They ask if there's anything new, and if there's anything else we can do."
The experience of survivors reaching out is common to many homicide detectives, who often form relationships with victims' bereaved family members. "They just want a sounding board," said Scott. "They want to know that you remember."
Detectives say they develop defenses to deal with the emotional strain. "But then," Purcell said, "there are those cases you just can't get over."
His voice trailed off, and he was silent for several seconds. Then he talked of unsolved cases that stick, some of which his wife knows as well as he does.
"It is a very powerful thing," he said. "You go to a scene, and you are the one who is supposed to make it right. People look to you. You have to make it right."
Exhaustion can be the result of all those unsolved cases, said Karen MacDonald, an LAPD psychologist.
MacDonald said she frequently sees detectives who come to discuss a family problem, but never get around to talking about it.
They can't get past their work. "Of course it's the first thing out of their mouths," she said. "They talk about it all the time--that unsolved case, the one that won't go away."
Homicide detectives are not especially prone to burnout or breakdowns, but they may become absorbed to the point of ill health.
"They don't know how tired they are getting," MacDonald said. "I've seen detectives who have fainted.... Or just exhausted people who fall asleep in their chair when they come in and talk to me."
Capt. James Bower, a supervisor in LAPD's 77th Street station, said he has to watch his homicide detectives closely--not because they slack off, but because they won't. They will work themselves to the point of no longer being effective if he lets them.
"I tell you, some days they are all up here with these raccoon eyes," he said. "I have to say, 'You guys are all outta here. Go home!'" Nationally, only about 63% of homicides result in an arrest, compared to 69% in 1998, according the Federal Bureau of Investigation. Detectives consider a case cleared when a suspect has been arrested.
In large urban areas such as Los Angeles, the rates are lower. Although officials say things are improving, LAPD's homicide clearance rate last year was about 50%, after hitting an all-time low of 44% two years ago.
That's down considerably from 1997, when LAPD cleared 70% of murders, and from 1970, when 79% were cleared.
Nationwide, larger cities where gang crime is concentrated have the lowest homicide clearance rates. In Chicago, for example, the rate dipped from 57% in 1997 to 47% last year.
The change reflects both the good and bad news about murder: On one hand, husbands and wives no longer kill each other with the frequency of years past.
But drive-by shootings and other forms of "stranger murders" remain a plague--and are less likely to result in arrests.
"What you have for evidence is a shell casing in the street," lamented Merriman. "And what you have for witnesses is people who are afraid to talk."
Purcell recalled perusing old files at the Sheriff's Department library, and his shock at how many listed suspects on the covers.
"I'd pull 'em and think, my gosh, look at these, they were solving all of them," Purcell said. "But then, so many were domestics, or cases that involved a relationship. So there was some reason for the murder."
Now there may be no clear relationship between suspect and victim, and the motive may be simply, "I live on that side of the street, you live over there, so I hate you," he said.
Gang-related violence in Southern California peaked in the early 1990s. In Los Angeles, 1992 was a pinnacle: 1,092 people were killed--119 in August alone, according to the LAPD. In the late '90s, murders in Los Angeles dropped to just above the 400 mark yearly.
But violence began rising again two years ago, and last year, the death toll in Los Angeles hit 587. The biggest increases have been in the toughest murders to solve: gang-related walk-ups, bicycle ride-ups and drive-bys.
For investigators, one of the most frustrating aspects of such cases is the lack of cooperative witnesses. Officers talk of arriving at the scene of a drive-by shooting to find 100 people lingering--but not one who will talk.
The phenomenon has led to a grim joke among detectives. Question: What's the difference between the cops and everyone else standing around at a murder scene? Answer: The cops are the only ones who don't know who did it.
The decline in clearance rates is also considered an unintended consequence of the movement to reform anti-gang units.
Two years ago, in response to the discovery of a cell of violent and corrupt officers in the Rampart area station, the LAPD restructured its old gang units, called CRASH, replacing them with so-called Special Enforcement Units, or SEUs, which operate under tighter supervision.
The cost was a loss of institutional knowledge about gangs. CRASH officers and homicide detectives had worked closely together, and "CRASH officers had been responsible for solving a vast number of homicide investigations," said Det. Clay Farrell.
Also blamed are the mass retirements of a post-Vietnam War generation of seasoned detectives.
As with any craft, detectives with the most time on the job tend to be the best. LAPD has lost 177 of its highest-ranking detectives to retirement since 1997. Their youthful replacements have yet to catch up, said Cmdr. Gary Brennan, a department spokesman.
Among the retirees is J.D. Furr, a 36-year veteran of the force.
Furr is all but legendary on the LAPD, described by Robbery-Homicide Capt. Jim Tatreau as, "a big, slow-talking guy with a Southern drawl--a cowboy who has never seen anything that has surprised him, and who has seen it all."
Furr doesn't know exactly what makes experienced detectives better.
But he said it took him years to learn to read a crime scene at a glance, and "to not throw too wide a loop, not look for something that's not there."
Such intangible losses are being felt in other departments as well, as they encounter similar age shifts in their ranks.
The Chicago Police Department, for example, has gone from the nation's fifth-oldest department to the fifth-youngest in the last decade, said Chicago Police Sgt. Robert Cargie.
At the same time, detectives in many departments fret that tight budgets and high caseloads make it hard to give each murder its due.
Under the best of circumstances, many urban homicide detectives work grueling hours. The physical strain of their work is exacerbated by its emotional toll. Burnout increases turnover.
Some agencies have begun seeking ways to improve.
The LAPD plans to hire a consultant to evaluate its detective operations. Like other departments, the LAPD has also started cold-case units, focusing on unsolved crimes.
But Tatreau said radical breakthroughs are unlikely. "Detective craft is not a mystery. We just have to give them time and resources to do their job," he said.
Scott, the county investigator, recently returned to the detective ranks after serving in another post for a year.
No sooner had she moved in than a stack of familiar files turned up on her desk. It was all her old unsolved cases. They had been shifted to other detectives, and, still unsolved, were now being reassigned back to her.
Scott was not surprised to see them.
Nor was she surprised at how clearly she remembered each one--she could still see the crime scenes in her head.
Unsolved cases are just like that, she said: "They follow you."