A street lamp on the center median marks the beginning of the quadrant. The officer starts there, pacing back to the other posts he's designated for himself. Letting the spool unroll, he loops the yellow evidence tape around the street lamp, under a bumper, over a mailbox, and through a picket fence. There is a pretense of familiarity in his attempts, the affected ease becoming more credible with each successive effort. Taking out a knife, he cuts the tape and ties it off back at the street lamp. The haphazard knots hold.

Just beyond the tape, gawkers give non-committal appraisals of the officer's efforts before settling back on the body of the young man on the ground. The officer lifts a section of the tape as the paramedics wheel the still clean and empty stretcher beneath it. Once cleared, the tape is dropped behind the procession. It sags a little closer to the ground.

The containment of a crime scene is a task that falls eventually on most cops-some with considerable frequency-and it usually starts as a baptism by fire.

Unfortunately, considering its import, relatively little crime scene preservation training has historically been given to officers. Yet the success of many a criminal prosecution can be traced back to how the first officers who responded handled the crime scene.

When it comes to recognizing what constitutes a well-preserved crime scene, few are more in a position to pass judgment than those who ultimately handle them: homicide investigators. Often, they show up long after you, the uniformed officer, have arrived on scene and coordinated its containment.

What makes for a good crime scene containment? What are the challenges you may face? And what do homicide investigators wish you knew?

Identifying What You Have

The crime scene can become a study in conflicting agendas. EMS services may have a shot at saving a life. Officers may have to clear adjacent rooms. Panicked or distraught witnesses may disrupt your evidence by taking flight. The haphazard clearing of an area and the assumption that suspects have vacated have proven problematic for Mark Lillienfeld, senior detective with the Los Angeles County Sheriff's Department's homicide bureau.

"We had a woman who was killed in front of a condominium," recalls Lillienfeld. "The house had already supposedly been cleared by patrol cops. Yet a second sweep from another group of deputies found another victim dead inside the house. It turned out there were two victims who had been killed by another neighbor.

Additional suspects-active participants, would-be getaway drivers-have all been found in and around crime scene containments in areas that supposedly had been cleared.

[PAGEBREAK]Effecting the Containment

Remember, what constitutes the true scope and nature of your crime scene may expand beyond that which is readily apparent.

Once you've identified the parameters of your crime scene, you have to physically define them. A cardinal rule is that it's easier to constrict a crime scene than it is to expand one.

"You're not going to screw one up by making it too big," says Lillienfeld. "Guys can be hesitant because of traffic, shy about making a scene a little bit larger than they were anticipating. But almost without fail, you then find physical evidence outside the scene's perimeter."

Greg Dagnan, assistant professor of criminal justice at Missouri Southern State University, teaches multi-level containment. He says the first level is the most basic: that of the crime scene itself. A second level-a second barrier-serves as a buffer zone, allowing for an area where command staff can park their vehicles and investigators can convene without interference. The third level constitutes the outer perimeter, where officers and vehicles can be deployed and road blocks effected.

Coordinating your resources and keeping track of their actions ranks high when it comes to attention to detail. Keep a homicide scene checklist and do things by the numbers. "Little things" such as the absence of a crime log have been successfully exploited by defense lawyers to create doubt as to who has accessed a crime scene and might have contaminated it.

David Newman conducts a variety of crime scene seminars for everyone from first responders to prosecutors and runs the Website www.insidethetape.com. He routinely makes the following recommendations to patrol officers:

"Officers should carry some type of marking devices for physical evidence. I've seen officers use empty Coke cans, business cards, or evidence slips. I encourage them to carry survey flags or things of that nature so that when they have to mark physical evidence they can do so properly so that what they use to mark evidence isn't confused with evidence itself.

"They should also carry with them some type of recording device besides just their cell phone, ideally some type of recording device that can store separate audio or digital files," Newman says. "We'd also like them to have a video camera so that if they arrive at a crime scene and they see something that might be temporary in nature and go away before investigators can get there at least they have a chance to document it. Also, by having an audio recorder instead of just handwritten notes they're able to be much more detailed in the documentation of a scene."

Once the crime scene is cleared of witnesses, victims, suspects, and paramedics, no one should cross the yellow tape and/or enter the crime scene without prior approval of homicide investigators. This prohibition includes the handling patrol unit, assisting units, supervisors, and local dignitaries.

Vernon Geberth is the author of what has been referred to as the "Bible of Homicide"-"Practical Homicide Investigation: Tactics, Procedures and Forensic Techniques." He is also adamant about the need for decisive containments.

"I don't care if you're a billionaire or a bagman," Geberth says. "The same rules apply. It's called constitutional law. What I want from first responders is to act like official representatives of the police department, lock the scene down, stop it in time, and prevent contamination."

Geberth cites ineffectual police presence as a major complication to the JonBenét Ramsey investigation.

"The bottom line is that they (the Boulder Police Department) did not conduct themselves like official first responders," Geberth states. "If you or I were called to the location of an alleged kidnapping and there was a ransom note in the house, what does that make the house? It makes the house a crime scene. That means that we own the house. We would have conducted a search, and we would have found the little girl's body, and all that conditional and transient evidence that was disturbed because the body had been moved multiple times after it was discovered would have been in place, intact, and they would have had an investigation."

Aggravations, Frustrations, and Underminers

At face value, preserving a crime scene doesn't appear to be a difficult task: You put up some crime tape. And you keep people out.

But it can be a lot more complicated than that.

The good news is that, generally speaking, a surprising amount of respect is extended to that flimsy trail of yellow evidence tape. But not everyone is so respectful of this implied force field, and any number of elements and emotions can threaten the integrity of your crime scene.

Perhaps no greater offender is to be found than the looky-lou cop who ventures into a scene with no reason to be there.

"I had an officer-involved shooting where a casing was found outside that had been carried out on the boots of a looky-lou," explains Lillienfeld. "At the same scene, I had three sheriff's department executives walk through a house. They had no reason to be in the house. I could give you a good briefing and you'd know exactly what went on inside the house."

Mindless acts by officers at a crime scene can also frustrate investigators. "I remember a crime scene where it was contained and I found saliva," Lillienfeld explains. "I thought I had DNA evidence. It turned out that one of the officers went into the scene and spit on the street. You'll also find cops putting cigarette butts out on the street, and even using a victim's phone inside a scene."

These are some of the reasons Lillienfeld feels some cops might best serve a homicide investigation by staying away. At the very least he believes in limiting the number of responders to a scene.

"Throwing a bunch of people at a scene is not necessarily the best way to handle it. You want the right people at the scene, people working together, people who are totally aware and understand the whole concept of the investigation so they know what they're looking for. The more people you have to coordinate, the greater the probability that something is going to go wrong," Lillienfeld says.

Another problem is the contamination of the scene by relatives and friends of the victims.

"We had a murder scene where a woman was killed inside a home," recalls Lillienfeld. "Her husband somehow got wind of it at work, and he came tearing up in his car. Nothing was going to stop this poor guy from going in and seeing his murdered wife. I'm in a suit and tie, and I'm on the ground wrestling with this guy, getting my butt kicked. We wound up hooking him up and booking him.

"It was really unfortunate. We had no intention whatsoever of charging this poor guy. You have the emotions, and you have to recognize that is part of the job and part of being mature," Lillienfeld adds. "Sometimes it happens; it isn't the greatest thing in the world for our image, but sometimes you have no choice. The guy contacted us later to apologize for ruining our clothing. He was just out of his mind with grief at the time and later came to his senses, which I think happens more often than not."

[PAGEBREAK]Flexibility, Adaptability, and Common Sense

If ever there is a situation that may call for flexibility, it is a homicide scene. Sgt. Dave Johnson of the San Diego Police Department's homicide unit notes that blind anal retentive adherence can unwittingly complicate the situation.    Continued on page 40

"If you're at the beach and the tide is coming up and you're facing the decision of letting the ocean wash the evidence away or not, you may want to take a picture of its original location then collect it as best you can," Johnson explains. "People get so afraid of contaminating evidence because it's a crime scene that they allow it to override their common sense. What's the option? Let it get washed away? You need to be able to prioritize. You may be able to get witnesses first, or collect evidence-or flip-flop that."

Geberth describes a volatile situation in which patrol officers must take action long before homicide investigators arrive on scene.

"You go into a social club where there's been a shooting," he says. "You temporarily have everybody neutralized. What are you going to do? Leave the guns on the floor and see who catches them first? No, you're going to secure the weapons. Oh, we didn't get a picture of it. Well, too bad you didn't get a picture of it. I have five or six combatants temporarily neutralized; I'm not going to leave the evidence in place before somebody grabs it, it disappears, gets lost or contaminated. So I picked it up and I took it. That's just common sense."

According to Newman, such common sense can be in short supply at a crime scene.

"We had two scenarios, both involving officers having to react to shooting scenes and inclement weather," Newman says. "One was an indoor homicide during a northeaster storm where there was also evidence outside in the front driveway and yard. The officer observed a cartridge casing outside and a mutilated spent bullet. Water was creeping up to the house at such a rapid pace that he had to react instead of waiting for investigators to get there. Using a digital camera, he took two mid-range photographs and two close-up photographs of the evidence as they lay on the grass then recovered them and placed them in his pocket, which is OK to do. Ultimately that evidence that he'd documented and recovered was used to reconstruct that scene and link the suspect to what took place.

"The other scenario involved narcotics investigators in the middle of a buy/bust in a parking lot that went south and resulted in a shooting with three suspects and three officers shot. A storm was approaching, and there were casings and handguns scattered literally everywhere. So officers that first arrived on scene were able to use spray paint cans to mark the locations on the pavement where the cartridge casings were recovered and they used numbers that corresponded to the evidence envelopes that the casings were placed in (#1, #2, #3, etc.). We were able to reconstruct the scene the next day when the weather cleared up because of that."

Professionalism at Crime Scenes

How you conduct yourself at a crime scene is a collateral concern. And as LASD homicide detective Paul Mondry notes, patrol officers can unwittingly complicate an investigation.

"Conversations, loose tongues, things that are said can all be a problem," Mondry says. "I had a murder investigation where comments made by the officers were overheard by people and led to speculation. It took on its own life when the papers were reporting things that didn't occur, citing it almost like it was gospel. In reality, it was just people who couldn't keep their mouths shut."

Things can get volatile on the front lines, and it helps to have sufficient manpower and a game plan in place.

"We're in the communication business," explains Lillienfeld. "Sometimes people are going to listen to you when you try to explain to them why you just can't let them touch or even see their loved one because of the transfer of evidence. You have to give them the big picture: 'Our job isn't going to just end here, and your grief isn't going to just end here. A week or a year from now, we're going to be in court and we're going to have hell to pay if I let you go hug your loved one.'

"Sometimes patrol cops have a hard time explaining that to people, even people who are calm and rational and not going crazy. Sometimes we don't take the time to do that."

Geberth also understands the emotions encountered at homicides. "There's a lot of tension, a lot of emotion, and a lot of anger. They scream, 'I want to see my son! I want to see my son!' My answer was always to say, 'Listen, I understand that you want to see your son. But I think under the circumstances that you should remember him the way that he was in life because right now this is not a good thing to see.' And that would work."

Clergy members are accustomed to dealing with bereaved individuals, and can serve as a buffer. Consider having one on hand.

Talk to the Detectives

You can do the best job containing the crime scene and still see your efforts prove for naught. Crime lab technicians have contaminated evidence with their own DNA. Homicide investigators have ignored pertinent evidence. Prosecutors have dropped the ball.

All you can do is what's expected of you-no more, no less.

How will you know you've succeeded? Some homicide investigators are more forthcoming than others. Geberth made a habit of writing commendations for uniform personnel who did a good job.

But not every investigator is so conscientious when it comes to dealing with the uniformed street cop, which is why prior to leaving the scene, you may want to take the initiative and ask them for suggestions for the future. Because while they might not otherwise say a word to you, they may nonetheless make comments behind your back.

Besides, as any investigator will tell you, while it's fine to count on dumb luck and dumber criminals, it's better counting on smart cops.