THE IMPORTANCE OF BLOOD was recognized centuries before its biological function was understood. “The blood is the life,” as Count Dracula told Jonathan Harker in Bram Stoker’s novel; if your “life’s blood” ebbs out, you will die. Patriots are “red-blooded Americans.” The aristocracy are “blue bloods.” An evil person has “bad blood” and an insane person “tainted blood.” Blood, after all, is thicker than water.
Blood is the one thing investigators are almost certain to find in abundance at crime scenes involving physical violence. The average adult body contains a lot of it, about five liters (ten pints). Most injuries release at least a bit of it. It remains liquid for quite a while after leaving the body, and whatever it lands upon it stains. A perpetrator is quite likely to take a bit of it away with him. As the criminalist Harry Söderman put it in his autobiography Policeman’s Lot, “Blood is a liquid which, in a crime of violence, seems to have an uncanny capacity to hide itself, only to reappear at a fitting moment and testify against the murderer. Blood will creep under the tiles of a floor, into the cracks of boards and the grain of wood, under fingernails; blood will linger in the water trap of a basin where the killer has washed his hands. It will cling beneath the top of a table where fingers have been thoughtlessly wiped. It splashes on clothing and into hair.”
Imagine that the police have a suspect in custody and that there are suspicious brown stains on his trouser legs.
“It’s paint,” he claims.
Is it blood?
“Okay, it’s blood. I was hunting and shot a pheasant.”
Is it human blood?
“Okay, it’s human blood. I had a nosebleed.”
Is it his blood, or is it the victim’s?
It took more than a hundred years of forensic research to find the answers to these questions.
Bloodstains are not stable but rather change with the passage of time. They are influenced by the effects of temperature, moisture, and sunlight. They are not always red or brown but can be altered by environmental factors in such a way that they may appear grey, tan, yellow, or even green. Fresh blood can be identified under the microscope—the erythrocytes (red blood cells) and leucocytes (white blood cells) show up clearly. But as blood dries, the two cell types clump together and cannot be differentiated. If the stain is not too old or too small, the red cells may be coaxed out again by washing the stain in a solution of caustic potash and alcohol. Sometimes this is successful, and sometimes not.
In 1853 the Polish physician Ludwig Teichmann developed a test for blood that was complex but effective when it worked. He found that if a bit of the suspected blood was dissolved in a mixture of saltwater and glacial acetic acid, and then warmed, crystals of hematin would form as a positive reaction to the presence of blood. The crystals are a sure sign that the substance is blood. Sometimes, if rust is present in the blood, the crystals may not form. But if they do form, the substance is blood.
Ten years later a German chemist, Christian Friedrich Schönbein, the discoverer of ozone and the inventor of the fuel cell, found that hydrogen peroxide would foam in the presence of blood. Even tiny amounts of blood would set off this reaction. But so would tiny amounts of semen, saliva, rust, and certain shoe polishes. So Schönbein’s test is a quick and good one for elimination purposes—if it does not foam, it is not blood. But if it does foam, it may not be blood and you must test further.
The reaction is set off by the blood enzyme catalase, which turns the hydrogen peroxide into water and oxygen. The oxygen is given off as a gas and thus causes the foaming. Catalase is the blood component that pulls oxygen out of the air in the lungs and delivers it to all the cells of the body. Its oxygen-grabbing ability is strong.
A quick test, though not a positive one, for blood in a dried stain uses tincture of guaiac, the resin of any of the six trees or shrubs of the genus Guaiacum, a subtropical evergreen with several varieties that are grown today as ornamentals in Florida and California. Guaiac is still used in a medical test that screens for minute traces of blood in feces.
The procedure in this case is to cut out the stain, lay it on a clean sheet of glass, moisten it with distilled water, and let it sit for a time. A technician then covers it with a sheet of filter paper cut to size, presses the paper down firmly with a glass rod, and waits a while longer. Then the technician takes up the filter paper and tests it with a few drops of an equal mix of tincture of guaiac and turpentine. The presence of blood will color the filter paper blue, as will a few other substances. As with the test for crystals of hematin, this is a useful test for the elimination of a suspected stain. But if the paper does turn blue, you will need additional samples of the stain for use in further testing.
By the end of the nineteenth century a wide array of tests for blood had been developed. The most reliable and certain of these was the spectroscopic examination of the stain. But very few forensic labs had access to a spectroscope, and there were still no tests that could differentiate human blood from animal blood.
The importance of a means of recognizing human blood from that of other mammals is very apparent, but is a problem that does not appear to be well understood. Some years ago Mr. Barreul, a chemist of Paris, became so skilled in the recognition of animal blood by the agency of chemical action in connection with his unusual acuteness of the sense of smell, that his testimony was taken in the Paris courts as positive evidence. We believe the process consisted in the addition of sulphuric acid to the blood, and the test consisted in the odor evolved during the heat resulting from the mixture. We don’t recollect whether this ability to detect included dried blood or not, but remember that it detected unmixed blood with great certainty, the blood of each animal evolving a peculiar odor.
—American Journal of Pharmacy, July 16, 1866
According to M. Barreul, when boiled in sulfuric acid cow’s blood smelled like the inside of a barn, sheep’s blood smelled like grass, and human blood smelled like sweat. Since few others could duplicate the feats of his remarkable nose, this investigative technique was soon abandoned.
One accurate, if slightly fallible, method of telling human blood from that of other mammals could be employed by chemists other than M. Barreul. If the blood was fresh and had not yet clotted, it could be differentiated microscopically by the size of its red blood cells. Birds, fish, and reptiles all have oval, nucleated (containing a nucleus) red blood cells. All mammals have circular red blood cells without nuclei (except for camels and llamas, which have oval cells, but still no nuclei). From mammal to mammal, these cells vary in size. Human erythrocytes have a diameter of 0.0003 inch (three ten-thousandths of an inch), cow cells average 0.00025, and goats 0.00015. It takes a good microscope and a good eye to read a difference of less than one ten-thousandth of an inch. Further, when blood dries the red cells are deformed, and it becomes difficult to restore them in a way that allows accurate determination of their size. A better test for human blood was needed.
The February 7, 1901, issue of the Deutsche medizinische Wochenschrift (German Medicine Weekly) contained an announcement by Paul Uhlenhuth of the Institute of Hygiene at the University of Greifswald that he had devised a test that would distinguish human blood from any other, no matter how small the trace. Uhlenhuth’s claim was greeted with profound skepticism. An assistant professor at a small, unimportant university had succeeded where some of the brightest and most respected men in medicine had failed? Unlikely.
But Uhlenhuth, in the best tradition of science, had stood on the shoulders of those who had come before him and peered in a slightly different direction. In 1890 Emil Adolf Behring and his co-workers at the Institute of Hygiene in Berlin had developed a method for immunizing people against diphtheria and tetanus. By injecting guinea pigs with a filtrate of the diphtheria culture from which the actual bacilli had been removed (a substance they called a toxin), they were able to induce a reaction in the blood of the guinea pig that would neutralize the diphtheria. And the guinea pig’s blood serum (the watery liquid remaining when all the cells and detritus are removed) could confer this protection to other guinea pigs, rabbits, and humans. They called this blood serum an antitoxin.
This breakthrough prompted the founding of serology, an entirely new branch of medicine. In the same year that Uhlenhuth announced his discovery, Behring won the Nobel Prize for his groundbreaking work.
The term “serology” originally meant only the study of serum, but so much more has been discovered about blood over the years that the term now includes all the various laboratory tests that identify antibodies, antigens, and the numerous other substances found in blood.
Uhlenhuth found that if he injected protein from a chicken egg into a rabbit and then, after a time, took some of the rabbit’s blood and created a serum, he could mix the serum in a test tube with chicken egg white and a cloudy precipitate would form and drift to the bottom of the tube. But it worked only for chicken egg white; when the whites of pigeon, gull, or turkey eggs were mixed with the serum, nothing happened. The injection of chicken egg protein into the serum had somehow primed it to differentiate chicken protein from that of any other bird. He quickly learned that the same thing happened if he used pigeon egg protein. When injected with pigeon egg protein, the rabbit’s serum would precipitate out the protein of no other bird.
When Uhlenhuth tried developing a serum with chicken blood instead of egg white, a flaky protein precipitated out and dropped to the bottom. Uhlenhuth had discovered how to create a serum that would react with the blood of one animal and one animal only. (There were some closely related animals whose blood was too much alike for the test to work—horses and donkeys, for example, and humans, gorillas, and chimpanzees.) His test succeeded even with small amounts of very old, dried blood as long as the blood was first dissolved in saltwater.
Uhlenhuth soon had serums made for his so-called precipitin test that would be specific for every animal imaginable. And he quickly developed safeguards for the test. After faulty results were obtained from serum made in another lab, he standardized the serums and insisted that his own institute, along with the Robert Koch Institute in Berlin, be the only official sources. He also strongly suggested that before each test of an unknown substance, a control test be conducted against a known sample. When some confounding results occurred due to the background material of the stain—tree bark, for example—Uhlenhuth added the suggestion that the underlying material be tested first in order to eliminate the possibility of a false positive. With these safeguards, the Uhlenhuth precipitin test worked infallibly every time.
On June 11, 1904, most of the body of a young girl was found tied up in a not-too-neat bundle of wrapping paper. The corpse floated in the Spree River between the Alsen Bridge and the Weidendamm Bridge, almost opposite the Reichstag in Berlin. The child’s torso, minus the head, arms, and legs, was clad in bloomers and a red woolen petticoat. Within an hour the body was identified as that of nine-year-old Lucie Berlin, youngest daughter of Friedrich Berlin, a cigar maker. She had been missing from her home at 130 Ackerstrasse for two days. The police immediately offered a reward of a thousand marks and ran the following notice in the newspapers and on broadsides posted around the city:
At 7:45 A.M. today the torso of Lucie Berlin, born in Berlin on 8 January, 1895, was washed up in front of the building at 26 Schiffbauerdamm. Head, arms, and legs of the corpse were severed with some sharp instrument. The girl was last seen playing in the yard of her home at 130 Ackerstrasse from noon to around one o’clock on the ninth of this month, and has been missing since then. She was tall for her age, was wearing a russet-brown wool dress, a black pinafore, white stockings, brown bloomers, buttoned shoes. She had a rectangular gold locket around her neck on a black velvet ribbon. Evidently the girl was the victim of an indecent assault. Persons who can offer information regarding her whereabouts from 9 June to 11 June, or who encountered her, are requested to communicate with the police at headquarters on Alexanderplatz or at any precinct.
—Police Chief von Borries
Berlin did not yet have an official medical examiner in 1904, so the child’s autopsy was performed by Professor Fritz Strassmann, head of the Academy for Instruction in Public Health, and by his associate Dr. Schulz. The child had probably been strangled, they reported. Her vagina had been torn by rough fingers, but probably after she was dead or near death through strangulation. She had died about an hour after eating her last meal of “pork, potatoes and cucumber salad.”
Murders were not common in this turn-of-the-century city of four million—there had been only thirty-eight in all of 1904. So the death and dismemberment of a young girl was front-page news. The headline in the Berliner Tageblatt read “Entdeckung eines Lustmordes” (“Discovery of a Sex Murder”). The Berliner Morgenpost published an extra edition and hung posters all over the city. Berliners were on the alert for “brat chasers,” as those adults who were overly fond of children were called. Several had to be rescued by the police from spontaneously formed mobs.
Police suspicion soon settled on Theodor Berger, a thirty-five-year-old junk dealer who was visiting his girlfriend, Johanna Liebetruth, a prostitute who lived down the hall from the murdered girl. In fact Berger was not actually visiting her; he was waiting in her apartment to welcome her home from a three-day stay at the women’s prison on Barnimstrasse. Berger had actually lived with her in the apartment ever since she had moved in six months earlier. The address on his identification document was a domicile occupied by another fellow. And Berger was not actually a junk dealer, but he hoped to become one some day. Aside from living off the earnings of Johanna, it was unclear how he made his living.
Several things pointed to Berger’s involvement. He knew the girl—she called him “Uncle.” Anna Müller, an eighty-year-old woman had seen Lucie on the stairs the day she disappeared and had noticed Berger ogling the girl as she passed his door. Frau Marowski, who occupied the apartment above Johanna Liebetruth’s, had heard a child scream “No!” somewhere below at around one in the afternoon. At 1:30 Herr Nölte and his wife, who lived below Liebetruth, had heard a loud series of thumps from above—“as though someone had fallen out of bed,” he told the detectives.
And then there was the interesting fact that on the very day Johanna Liebetruth got out of prison, Theodor Berger had suddenly agreed to marry her, something she had been after him to do for eighteen years. Was marriage perhaps the price of her keeping her mouth shut?
Two days after the torso was found, some boys fished a child’s head and two arms out of the Charlottenburg ship canal. The body parts were wrapped in a copy of the Berliner Morgenpost dated June 9, the day Lucie went missing. Lucie’s right leg was soon found in another canal and her left leg in the Spree. Now most of Lucie’s body was assembled. Someone had gone around distributing parts of Lucie in bodies of water all over Berlin. But was it Berger? The evidence against him—the best if not the only suspect—was circumstantial and far from convincing. The police searched the Liebetruth apartment for signs of blood; they pressed large pieces of blotting paper soaked in hydrogen peroxide or tincture of guaiac everywhere. They got a few reactions that might have been blood, but nothing to indicate the large amount of blood that must have flowed from poor Lucie’s dissected body. And there was none on what were usually the most incriminating spots—the sink drain, the rug, the kitchen knives, and articles of clothing.
It occurred to the police to wonder what the dismembered body had been carried in. Surely the murderer had not wandered about Berlin with newspaper-wrapped body parts under his arm. What might he have used? Johanna Liebetruth told an investigator that when she returned from jail a large wicker suitcase was missing from her rooms. At first Berger had denied knowing anything about it, but when she pressed him he had shamefacedly admitted that he had picked up a girl when Johanna was away and had paid for her services with the wicker suitcase. He didn’t know the girl’s name and had not seen her before or since. Even Johanna was not sure she believed Berger’s story.
The police let it be known that they were looking for a large wicker suitcase that was probably in one of the bodies of water around the city. On Sunday, June 26, twenty five days after Lucie’s disappearance, a bargeman named Wilhelm Klunter reported finding it. He had actually fished it out of the water some days before, but because he never read a newspaper he was unaware that the wicker suitcase was wanted until told about it by his aunt.
Liebetruth examined the suitcase and said it was hers, pointing out several identifying features. And there were dried, dark red spots on the side of the suitcase that might well be blood. But was there any way to tie the suitcase to Lucie Berlin’s body? Proving that the spots consisted of human blood would be a large step in that direction.
Dr. Schulz had practiced the Uhlenhuth precipitin test, and here was an opportunity to put his new skills to use. He scraped one of the stains off the wicker and dissolved it in distilled water. Following Uhlenhuth’s instructions to the letter, he also made solutions of scrapings from an unbloodied bit of the wicker suitcase as well as a known solution of human blood.
When he added a measured amount of diluted serum containing antibodies for human blood to these solutions, it took only seventy seconds for clouds of precipitate to form in the tubes containing the wicker stain and the known blood sample. Only the plain wicker sample stayed clear.
The stains on the suitcase were from human blood.
On December 23, 1904, after a twelve-day trial, Theodor Berger was found guilty of the murder of Lucie Berlin.
Several years before Berger’s trial another important step in blood identification had been taken, a step that for the first time allowed for safe blood transfusions. It saved the lives of countless surgery patients and trauma victims. On November 14, 1901, Dr. Karl Landsteiner, an assistant at the Department of Pathological Anatomy at the University of Vienna, published a modest paper in the Wiener klinische Wochenschrift (Vienna Clinical Weekly) entitled “On Agglutination Phenomena of Normal Human Blood.”
Dr. Landsteiner had discovered that some human blood did not mix well with other human blood, that a serum of one person’s blood might make another person’s blood agglutinate, that is, clot up. Landsteiner had no idea why this happened, but he was determined to find out. He went around his department taking blood from everyone who would donate and tested each sample against the others.
It took Landsteiner a while, but he finally determined that there were four blood types, which he eventually named A, B, AB, and O. The letters indicate the different types of a protein called an antigen that is found on the surface of red blood cells. Type A blood cells have the A antigen, type B have the B antigen, type AB have both, and type O have neither. And because blood serum contains specific antibodies that react with (or not) the different types of antigens in the blood cells, this means that:
Type A antibodies will agglutinate Type B blood.
Type B antibodies will agglutinate Type A blood.
Either serum will agglutinate type AB blood.
Neither serum will agglutinate type O blood.
What this means practically is that if you know what blood type a person has, you know what types of blood you may safely transfuse into him. Type O blood may be given to anyone; type A blood may be given to people with type A or AB blood; type B may be given to people with type B or AB blood; type AB blood may be given safely only to people who have type AB blood.
An additional complication, discovered by Dr. Landsteiner and Dr. Alexander Wiener forty years later, is the Rh blood factor, another protein found on the surface of red blood cells. It is named after the Rhesus monkeys used in early tests. Roughly 85 percent of the population are Rh positive (Rh+), that is, they have the Rh factor in their blood; and 15 percent are Rh negative (Rh–).
This has practical consequences in pregnancy. When an Rh negative mother carries an Rh positive baby—which happens if the baby inherits the father’s Rh positive blood type—the mother’s immune system may develop antibodies against the blood of her own baby. Usually this does not affect the first pregnancy. But if during a second pregnancy the fetus is again Rh positive, the antibodies developed during the first pregnancy can mistake the fetus for a foreign substance, enter it through the umbilical cord, and attack the baby’s blood. This may cause severe jaundice and anemia in the newborn child and may even result in the child’s death. Now that the condition is understood, an Rh negative mother may take several precautions that will protect her child.
For forensic serologists, the Rh factor provides one more handle with which to identify an evidential blood stain. When added to the O, A, B, and AB blood factors, it is useful for elimination—that is, if none of the blood factors matches the suspect’s, it is not his blood. But it does help narrow down blood types into small enough groupings to tie a given suspect to a crime. If a blood sample is type O, Rh positive, roughly forty people out of every one hundred in the United States match it. If it is AB negative, the rarest blood type, only three people in every ten thousand match it. Still, this means that in the city of Los Angeles alone there might be three thousand matches.
According to the American Red Cross, the breakdown in frequency of blood types in the United States is as follows:
O+ | 40 percent |
O– | 7 percent |
A+ | 32 percent |
A– | 5 percent |
B+ | 11 percent |
B– | 1.5 percent |
AB+ | 3 percent |
AB– | .05 percent |
In the past several years a variety of secondary blood differences have been found, secondary because they do not affect the safety of blood transfusions and are of interest only to geneticists and forensic serologists. Some of these secondary factors are the M, N, MN, and P factors, which in certain combinations have been linked experimentally to a tendency to hypertension.
There are other factors that are differentiated by electrophoresis, a technique in which a cotton thread is saturated with the sample blood and then embedded in a thin gel. When a direct current is passed through the gel, the various components in the blood move down a glass plate at slightly different speeds. When the current is removed, the plate is stained and the blood factors now appear as dark bands spread out along the plate. Unlike ABO typing, which has been used successfully on ancient mummies, or DNA, which can persist for eons, this technique works best with comparatively fresh blood, and the differences will fade away after only a few weeks.
Other secondary blood factors are:
Adenosine Deaminase (ADA)
Adenylate Dinase (AK)
Erythrocyte Acid Phosphatase (EAP)
Esterase D (EsD)
Group-Specific Component (Gc)
Haptoglobin (Hp)
Hemoglobin (Hb)
Phosphoglucomutase (PGN)
Transferrin (Tf)
If tests for these factors are available, law enforcement can narrow its range of suspects to well under i percent of the population. This comes nowhere near the one-in-ten-million-or-better possibilities of DNA, but these tests may be performed more quickly than DNA screening. They are very effective in eliminating suspects.
In addition to deductions about the source and composition of the blood left behind at a crime scene, observations of the blood’s position at the scene may also yield a great deal of information. Blood that has been dropped, dripped, spattered, sprayed, or splashed in a particular direction and at a particular height tells the story of the crime to a trained analyst. Given the right spatters, it is possible to determine where the victim and the killer stood, which hand the killer used, whether or not the victim fought back, whether anyone else was in the area, and other details that may eventually prove relevant.
In the early morning hours of July 4, 1954, the Bay Village, Ohio, police were called to the home of Dr. Samuel Sheppard, a wealthy and popular osteopathic surgeon. Downstairs they found a battered and barely coherent Dr. Sheppard being tended to by the mayor of Bay Village, Sheppard’s next-door neighbor. Upstairs in a bedroom they found the body of Marilyn Sheppard, Dr. Sheppard’s wife. She had been savagely beaten to death.
Bay Village, an exclusive suburb of Cleveland, had never before experienced a crime even remotely like this one. The murder quickly became the subject of intense interest and even passion. Sheppard said he had been sleeping on the living room couch when he was awakened by the sound of Marilyn’s screams coming from the bedroom. He rushed upstairs but was knocked down—and out—by a “white figure” on the staircase. When he came to, he groggily went into the bedroom and saw that Marilyn was dead. As Sheppard went downstairs, he saw the so-called white figure leave the house through the back door. He gave chase, then grappled with a “bushy-haired form” before he again lost consciousness. The next thing he remembered was waking up sometime later on the beach (his house faced Lake Erie). He rushed home and ran upstairs to find that Marilyn was indeed dead in the bedroom. He then went back downstairs, called his next-door neighbor, Mayor John Spencer Houk, and then collapsed on the living room couch. Houk and his wife hurriedly dressed—it was then around 5 A.M.—and rushed over. Houk tried to rouse the dazed and confused Sheppard while his wife went upstairs where she found Marilyn Sheppard’s battered body.
In a room drenched with blood, Cuyahoga County Coroner Sam Gerber found Marilyn lying face up on the bed. There were more than twenty deep cuts to her face and body. Under Marilyn’s body he found a pillowcase with a bloodstain on it that seemed to him to have the outline of a surgical instrument. The specific instrument could not be identified, but the term “surgical instrument” seems to have hypnotized the police. They were already settling on “Dr. Sam,” as he was known locally, as the murderer of his wife Marilyn.
When Sheppard went to the sheriff’s station for a voluntary interview, six days after the murder, the police were finished settling. “Did you ever,” they sprang at him, “have an affair with a Sue Hayes?”
“We’re just good friends,” he replied.
On July 16 Louis B. Seltzer, editor of the Cleveland Press, printed an editorial headed “The Finger of Suspicion,” which deplored “the tragic mishandling of the Sheppard murder investigation” and suggested that Sam Sheppard hadn’t been arrested yet only because of the incompetence of the Bay Village police and the influence of the Sheppard family. On July 20 Seltzer placed an editorial on the front page, under the five-column headline “Getting Away with Murder,” which shamed the Bay Village Council into asking the Cleveland police to take over investigation of the case.
At the coroner’s inquest, a friend of the family, Nancy Ahern, was pressured to admit that Marilyn Sheppard had told her of Sam’s affair with Susan Hayes and had said she was afraid Sam would ask for a divorce.
On August 16 a grand jury met to consider the evidence against Sheppard. The next day he was arrested and charged with the murder of his wife.
The trial began soon after the jurors took a tour of the Sheppard house, where they saw all the blood in the bedroom. Dr. Lester Adelson testified for two days that Marilyn Sheppard had been beaten to death. Patrolman Fred Drenkan testified that he had heard Sheppard’s story about fighting with a bushy-haired man but did not believe it. Coroner Sam Gerber told the jury about the bloody pillowcase, declaring, “In this bloodstain I could make out the impression of a surgical instrument.” The pillowcase was handed over to the jurors to examine.
A fingerprint expert testified that he found Sam Sheppard’s left thumbprint on the headboard of Marilyn’s bed. He agreed on cross-examination that it could have been there since well before the murder. After a passel of expert witnesses, the prosecution put Susan Hayes on the stand to testify about her affair with Sheppard, and then rested.
The defense had Sheppard’s brother, Dr. Steven Sheppard, testify to the extent and seriousness of Sam’s own wounds—but since Steven was Sam’s brother, he may not have convinced the jury. Sam Sheppard took the stand and told about the murder night’s events, but his wooden delivery made him a bad witness. In cross-examination the prosecutor concentrated on Sheppard’s extra-marital affair and occasional dalliances, and finished by asking, “Isn’t it a fact that you beat your wife to death?”
“No, sir,” Sheppard replied.
It took the jury eighteen ballots to find Sheppard guilty. After his conviction, the defense was for the first time allowed to examine the crime scene. Bill Corrigan, Sheppard’s defense attorney, had not pressed to get the keys to the house during the trial, not realizing the importance of the blood evidence. When the prosecution refused to hand them over, he had not protested. But now that the trial was over he decided to find out if an expert could tell what had happened that night by examining the bloodstains. Corrigan made a long-distance call to the University of California at Berkeley and spoke to Dr. Paul Leland Kirk.
Dr. Kirk arrived in Bay Village on January 22, 1955, eight months after the crime. He examined the prosecution’s exhibits: the pillowcase with the “surgical instrument” bloodstain; Dr. Sheppard’s trousers; and the wristwatch Sheppard had been wearing, which had moisture inside it and a bloodstain on it.
Even eight months after the crime Dr. Kirk was able to reach a closely reasoned and intensely detailed conclusion, one that was vastly different from the one reached by the police, the prosecuting attorney, and the jury.
Dr. Kirk recreated the crime from the blood spatters in the bedroom. The blood spots on two of the walls were caused by the direct battering of Marilyn’s head, and those on a third wall were spatter marks from a swinging weapon. A heavy flashlight, or something similar, was probably the weapon used. There was no indication of any “surgical instrument”—the stain on the pillowcase had been caused by its being folded while wet with blood.
There was a blood void—that is, an absence of blood—on one side of the bed where the killer must have stood. Considering the amount of blood everywhere else, the killer would have carried a lot of blood away with him. Sheppard showed no such massive spatter on himself or his clothes. Dr. Kirk also determined that the killer had held the weapon in his left hand. Sheppard was right-handed.
Despite this and other indications of Sheppard’s probable innocence, the defense’s request that Sheppard be granted a new trial based on new evidence was denied. All this evidence, the court decided, should have been presented at the first trial. The fact that the defense was locked out of the murder house until after the first trial the Ohio appeals court found irrelevant.
Sheppard spent nine years in prison before finally being granted a new trial. By this time his attorney had died and attorney F. Lee Bailey, later to be famous, had taken over as his lead counsel. At his second trial in 1966, Dr. Sam Sheppard was found not guilty. A strong suspect for the murder came to light, but he died before any action was taken.
As Dr. Kirk said, “No other type of investigation of blood will yield so much useful information as an analysis of the blood distribution patterns.” But it takes training and experience to analyze blood spatter properly. The tendency to see in the patterns what the investigator hopes or expects to see must be rigorously resisted.