Blood Secrets: Chronicles of a Crime Scene Reconstructionist (18 page)

Investigators dug deeper into the Greineders’ private lives and unearthed the kind of dirt tabloids dream about. Dirk Greineder, it seemed, had a secret Internet sex life, frequenting chat rooms of couples looking for threesomes, ringing up massive phone bills to porn lines, and paying prostitutes for motel sex. In fact, he called one the day after his wife’s death. Greineder claimed he was ashamed of his salacious side, but the fact that his wife had lost interest in sex a decade earlier had forced him into it. Police and the DA’s office thought it more likely that the doctor longed to get May out of the way so he could pursue his porn obsession freely. They theorized that when she found his condoms and self-prescribed Viagra and started grilling him about them, he snapped.

Prosecutor Richard Grundy asked me to examine the evidence and give my opinion about which side of the story it bore out. I flew to Massachusetts and spent three days studying the bloody items recovered from the crime scene. What I found made a strong case against Greineder. His story just didn’t fit the blood on his clothes.

For starters, the front of the yellow Windbreaker he wore in the park that day was speckled with more than ten of the minuscule blood dots characteristic of medium-velocity spatter—precisely the pattern that lands on a killer’s clothing during a blunt-trauma murder. They were hardly the superficial blood transfers that might graze a panicked husband who stumbles on his wife’s dead body. More of the same spatter dotted his shirt, his pants, and his Reebok sneakers.

We sent the jacket to a forensics lab in King County, Washington, where tests also revealed cast-off stains on the back. That told me Greineder had swung the bloody hammer repeatedly, inadvertently flicking spatter onto himself as he killed May. Though the cast-off evidence was ultimately ruled inadmissible in court, the Windbreaker had plenty more to tell us.

Bloody hair and clothing transfer patterns suggested a dead or unconscious person’s head had rested against its sleeves and shoulders—exactly what would have happened if Greineder had dragged his wife’s body from behind. Sure enough, drag and heel marks in the woods suggested May had been moved ten feet or more. The shoe size was similar to Greineder’s.

Perhaps the most telling evidence of all were the bloody grab marks on the Windbreaker’s sleeves—transfer marks in May’s blood that would be consistent with the dying woman clutching her husband’s clothing as he bludgeoned her to death.

Fortunately, the police took a photograph of Greineder’s glasses before he left the crime scene. (He refused to surrender them that morning but turned them in later after they had been wiped clean.) We enhanced the image digitally and saw a large bloody smear with a dimpled dot pattern that matched the surface on the fingers of the bloody gloves.

Grundy called a number of witnesses, including Massachusetts State Police lieutenant Kenneth Martin, a blood spatter expert who provided testimony about the physical evidence against Greineder. My testimony followed Martin’s and reinforced his interpretation of the blood patterns in question. For my presentation in court, I dressed a life-size mannequin in the actual clothing Greineder wore on the morning of the murder and conducted a number of demonstrations with it to show the jury the kinds of actions that would most plausibly have produced the bloodstains on Greineder’s clothes.

Despite a vigorous defense and a trial that lasted more than five
weeks, Greineder was found guilty of first-degree murder and sentenced to life in prison without the possibility of parole in June 2001. He requested a new trial five years later but was denied.

High-velocity blood spatter
stains occur when something hits blood with tremendous force and atomizes it into a fine mist of airborne particulates. Though it is frequently accompanied by massive amounts of pooled blood from a victim’s wounds, the high-velocity mist itself leaves droplets so tiny that they are often imperceptible to the naked eye.

High-velocity blood spatter

Most high-velocity impact patterns you find at crime scenes in the United States are caused by gunshots, but explosives, car accidents, and injuries from heavy machinery like circular saws and chain saws create high-velocity mist, too. Remember the collection of minuscule
blood droplets embedded with brain tissue and fiber that we found covering the grease-caked engine of Eric Humbert’s car in the Green Thread Mystery? They were a perfect example of high-velocity spatter. Another was the incriminating dot pattern on David Duyst’s shirt in the Sandra Anne Duyst “suicide,” which, as you know, turned out to be a murder.

To visualize the effect of high-velocity spatter, think of filling an aerosol can with hairspray dyed red and then spraying it onto a mirror or a countertop. The gunshot sends bloody mist traveling through the air even faster than a spray can. If you’re a movie fan, picture the wood chipper scene in
Fargo
. The snow sprayed bright red provides a relatively accurate representation of what high-velocity blood spatter stains look like.

Most high-velocity blood spatter will travel in the direction the shot was fired, giving a crime scene reconstructionist solid data to use in understanding who stood where when the gun went off. When a bullet goes through a victim, the exit wound produces a mist of
forward spatter
, too. Exit wounds from gunshots make a conelike shape, as if the blood had been sprayed out through a megaphone.

Depending on the weapon, a sort of amorphous cloud of red mist can also rebound toward the source of the injury. It’s called
blowback
or
back spatter
. The Alan Gell Bug Case is a good example. We knew from the high-velocity back spatter in the door frame that the killer fired from the hall, which led us to conclude that suspect Crystal Morris’s story about Alan Gell emerging suddenly from behind the bedroom door and firing a double-barreled shotgun was a fabrication.

Because most of the droplets in high-velocity blood spatter are fine and lightweight, they lose momentum quickly in the air. That means they don’t travel as far as medium-velocity spatter. No matter how powerful a gun is used, the bloody mist it produces will land
only three to four feet from the source of the blood, though there are usually some larger, heavier drops that fall farther away.

More than one red herring can throw a seasoned detective off track when it comes to high-velocity blood spatter. Flies love to lay their eggs in blood, for instance. And when they walk around in wet blood, their excrement and their tiny footprints leave a pattern of dark, round specks that to the untrained eye looks a lot like the high-velocity mist from a gunshot. It often gets misidentified. Crime scene investigators will examine it and say, “Well, the killer had to be standing here.” But in reality, insects were responsible. How do you tell the difference? Under a microscope, you’ll spot the signature Q-shaped marks the insects leave when they regurgitate. Incidentally, scientists can actually pull DNA out of blood that has been through a fly’s digestive system to identify a killer or a victim.

Another pattern that often misleads crime scene investigations is expirated blood—blood that an injured person has exhaled or coughed out. (Some books on blood pattern analysis mention sneezing as a third source of expirated blood, though in more than forty years of crime scene investigation, I have never seen an injured person sneeze out blood.) It can come out through the mouth, nose, or even through severe wounds in the lungs or trachea. It produces a mist very similar to the type a gunshot wound creates. However, the tails of each droplet are blunt, the blood has air bubbles in it, and the pattern it makes is chaotic and random, as if the blood droplets have been spinning through the air in every direction. Gunshot spatter, on the other hand, produces a neat arc or fan of minuscule blood droplets with the
sharply narrowed spines of each pointing in the same direction. With experience, you learn to recognize the distinctive little round circles and voids in the blood and to look for mucous strands to confirm that blood was expirated. You can vet your theory by asking a crime lab to test a sample of the blood to see whether there is saliva in it.

I was asked to consult on an interesting case in Yonkers, New York, in the 1990s involving a woman whose husband was released from the penitentiary and then headed straight home to murder her. The man stabbed his wife in the back with a butcher knife, and she died while struggling to get out the front door of her apartment. The positioning of the body and the multitude of bloody hand transfers smeared along the inside of the door frame testified to that. But the DA’s office asked me to explain what the rest of the blood spatter meant. There was an abundance of high-velocity mist on the door. Didn’t that suggest that the man had shot her in addition to stabbing her? If so, why had the autopsy found no gunshot wound? Fortunately, I knew enough about expirated blood by that point to recognize the turbulent, irregular patterning it creates and to look for telltale mucous strands to confirm my suspicion. The knife pierced the woman’s lungs, and in her frantic struggle to escape she was breathing hard, almost panting in her last few minutes of life—exhaling blood all over the door and the wall near it.

It was just one of many cases I’ve worked on where high-velocity mist could mislead investigators as easily as it could lead them to the truth. Here’s another.

There was no question that Tyler Opperman was dead. The question was how he got that way. His wife, Casey, twenty-seven, swore she
had been in the bathtub of their home in Cincinnati, Iowa, at around three o’clock in the morning on January 27, 2008, when she heard a thump in the bedroom outside the bathroom door. She called to Tyler to ask him what had made the noise. When she got no answer, she went to see for herself. There was her twenty-three-year-old husband, lying at the foot of the bed, blood leaking out of his head, still holding the .22-caliber rifle he had just used to commit suicide.

Tyler Opperman’s family was hardly the first to have trouble believing that someone they loved had killed himself, though they had more reason for skepticism than many other grief-stricken families—namely, the fact that Casey’s first husband, twenty-eight-year-old Brad Tuttle, had also killed himself with a single gunshot wound to the head two years earlier in nearby Green City, Missouri. It didn’t help that Opperman’s new widow wasn’t exactly the sympathetic girl-next-door type, by many accounts. In fact, on the night Tyler Opperman died, Casey fractured her nose in a bar fight with another woman and the couple spent some of their last hours together at the emergency room.

The police and the crime lab couldn’t reach a unanimous decision about the cause of death, partly because of the puzzling blood patterns in the couple’s bedroom. Opperman’s was the only DNA on the gun, and his blood alcohol level was too low to suggest he might have been unconscious when he died. But blood spatter had ended up around the corner of a nightstand. How? Why were Opperman’s socks and the floor near his body speckled with what looked like back spatter? What did the voids and pooled blood underneath him mean? And how had he gotten blood transfer stains onto his clothing? Had someone moved his body? Did it suggest an angle of impact that no suicide could manage?

Sheriff Gary Anderson called me. I flew to Iowa and scrutinized the crime scene photos from the minuscule one-story blue cottage where the death occurred. The high-velocity spatter was tricky, but
ultimately it all pointed to one inevitable explanation, based on my knowledge of blood patterns: Tyler Opperman sat on the edge of his bed, placed the rifle between his legs, pointing it upward and pinching it between his knees to steady it, then put the end inside his mouth before pulling the trigger.

How could we be sure?

First, the powder deposits and blood stippling on the roof of the dead man’s mouth provided concrete evidence that there had been intraoral contact with the end of the barrel.

Second, the distinctive blood spatter on the victim’s clothing gave us enough solid data to re-create his position accurately. The inside of Opperman’s right sock and pant leg were blood-spattered. So were the outside of his left sock and pant leg. Yet there were blood-free voids on the inside of the left sock and pant leg as well as on the outside of the right ones. This told us that after the .22 discharged, Opperman’s head and torso slumped to the left, beyond his left leg and over the edge of the bed. His body remained upright for a number of seconds—blood dripping from his mouth and nose onto his clothing and the floor nearby—until the force of gravity finally caused him to fall and make the thump that his wife heard. (Strange as it might sound, it’s not uncommon for a seated gunshot victim to remain upright temporarily as Opperman did.)

During the moments that Opperman’s body stayed perched on the bed with his head hanging forward, his blood dripped enough to create a blood-into-blood pattern with satellite spatter on the floor that could easily be mistaken for back spatter pointing away from him. Finally, as he fell he brushed the edge of the swivel nightstand, which spun around so that the spattered side was facing away from him. He fell into his own wet blood and smeared some of it onto his clothing, creating the puzzling transfer stains and explaining how so much blood ended up underneath his body.