American Sherlock

by Kate Winkler Dawson

  “I have long held the opinion that in spite of his apparent altruism,” Oscar wrote a friend, “there was in his makeup an element of selfishness and egotism.”

  Osborn had asked August Vollmer for a teaching position at UC Berkeley without talking with Oscar—a breach in courtesy. Osborn’s classes would overlap with Oscar’s course on forged documents, and his instruction would tread on Oscar’s territory and threaten the job the criminalist needed so much.

  “I do not yet know whether to look upon the action as hostile or merely arrogantly altruistic,” he wondered to a friend.

  Oscar Heinrich was compiling a long list of professional enemies, perhaps a bad decision for an expert who leaned heavily on his strong reputation and personal recommendations.

  * * *

  —

  Oscar adjusted the oculars several times and then flipped the dial to increase the magnification. He peered through the lens at hundreds of blue-salt-and-pepper threads soaked with blood. He pivoted the eight-inch square of carpet, another clue from El Cerrito. It was early January 1926, almost six months after Bessie Ferguson’s murder, and Oscar Heinrich was still trailing far behind her killer. But he felt as if he was getting closer. He had to be closer, because the woman’s mother called on Oscar often enough to laden him with guilt. He was a parent, so he greatly sympathized. He squeezed a pair of metal tweezers and gently removed a curious substance.

  “I found impressed in the fibres a tiny fragment of material which has been tentatively identified as dental cement of the kind used in making dental impressions,” he wrote in his notes.

  There was dentist modelling wax embedded in the carpet square intermingled within the murder victim’s clothing. Oscar opened a container holding a gold crown that belonged to Bessie Ferguson. He looked at it under a magnifying glass first and then under a microscope and made a remarkable finding—tool markings made by a professional dentist.

  “These dental fragments are in harmony with the training required to perform the dismemberment and particularly the dissection of the upper jaw from the skull,” he wrote.

  Oscar searched for his notes about Bessie’s fatal injury, a hit to the top of her head that had caused multiple fractures. “Such an injury if it occurs in a dental office could easily be inflicted by a dentist upon a patient recumbent in a dental operating chair,” he noted.

  The killer was a dentist, a man with a medical background but limited surgery skills. Oscar reread his notes on the case. Ferguson’s list of paramours and admirers included two dentists. He was inching closer to her killer. Oscar was confident that Bessie’s murderer was a dentist—but which one of the two?

  Oscar reviewed his list of suspects and underlined just one: Dr. C. C. Lee, a Chinese dentist who owned an abandoned building just across the street from Bessie’s family home.

  * * *

  —

  It had been ten months since Bessie Ferguson was bludgeoned and dismembered. It had been such a long wait for her mother . . . and for Oscar. He was desperate to close the case now—he refused to admit he had failed. He homed in on one man, a neighbor who fit the profile of her potential killer. The other suspects, a short list of men who had loved or lusted over Bessie, were cleared—but not without repercussions. Frank Barnet, Alameda County’s sheriff for more than twenty years, lost his bid for reelection because of the Ferguson case.

  “Dr. Lee,” Oscar scribbled on his notepad.

  The criminalist confirmed that Lee owned a garage along with an empty house right across the street from Bessie’s parents’. He claimed to be a dentist, but there was no proof he had a medical education. But he did have direct contact with Bessie. Police found his shredded business card in her bag, and they discovered that his wife had often visited with her when Bessie returned to her parents’ home.

  Oscar was nearly obsessed with the case, even though he was embroiled in so many others. The criminalist hired a newspaper reporter from the Oakland Tribune to surveil Lee’s home, but the journalist never spotted him. After almost a year of investigating, lab tests, and interviews, Oscar Heinrich finally admitted defeat in the case of Bessie Ferguson. Dr. C. C. Lee, the mysterious dentist, appeared to be a phantom, an elusive suspect who might have gotten away with murder.

  “I am not prepared to say that he has committed this crime but I do believe that no investigation of this case will be complete without investigating this man,” Oscar solemnly told investigators.

  Throughout his forty-year career, there would be a handful of cases that nagged Oscar—Bessie Ferguson was one of the most painful. In 1927, two years after she was murdered, he was drawn into a case that seemed so familiar. A hiker traversing a trail in El Cerrito noticed a shallow grave filled with human bones. Police delivered another package to Oscar as they did with the Ferguson case—this one also contained a jawbone.

  Oscar returned to El Cerrito and knelt near the burial spot, an area of the swamp that was very close to where Ferguson’s ear and scalp were found. This victim was murdered, burned, and then buried. The two cases might have been connected, two people, both the prey of one killer who used the same dumping ground. Both investigations remained whodunits—Oscar Heinrich was never able to solve either case, so he had failed both victims. He would never forget Bessie Ferguson.

  10.

  Triggered:

  The Case of Marty Colwell’s Gun

  It is of the highest importance in the art of detection to be able to recognize, out of a number of facts, which are incidental and which vital. Otherwise your energy and attention must be dissipated instead of being concentrated.

  —Arthur Conan Doyle,

  The Adventure of the Reigate Squire, 1893

  Martin Colwell stood at the door of the cottage on Pennsylvania Street. He reeked of alcohol, as usual—it had been his vice for years. The police in Vallejo, California, had written his name on their offender blotter for different reasons, most notably assault and burglary. The state prison had hosted him for three terms since his youth. Martin “Marty” Colwell was a mean drunk, a ruffian who rankled police and issued threats to intimidate just about everyone else.

  And now he was furious over yet another betrayal. As he pounded on the cottage’s door, he held the .38-caliber revolver in his right hand. He focused his eyes ahead—he readied himself.

  It was December 19, 1925, just days before Christmas. The door opened, and John McCarthy, Colwell’s former employer, staggered into the doorway. Blood was sprayed across his shirt. Colwell heard moaning, saw McCarthy’s wound, turned, and ran. McCarthy lurched onto his front stoop, begging for help. Police responded quickly and tried to save his life, but it was too late. McCarthy, a loved and respected small-business owner, muttered some final words to investigators, a simple phrase that seemed likely to condemn his killer.

  “I fired Colwell.”

  It seemed like an open-and-shut case, but Colwell quickly made a savvy decision: he hired an impressive defense team. The district attorney, panicked, phoned Oscar Heinrich. Colwell would certainly murder again if he wasn’t convicted, the DA feared.

  The press ignored the murder. This wasn’t a beguiling story about a devious chemist or a deranged baker, but Colwell’s trial was crucial because it offered Oscar something he desperately needed—redemption.

  The remainder of the 1920s had produced a string of cases that challenged Oscar’s scientific acumen and his investigative skills. He was one of the first to use ultraviolet light to reveal blood. Oscar used deductive reason and poison tests to prove murder by strychnine when toxicology was still in its infancy. He honed his technique in blood-pattern analysis after the shooting death of a wealthy wife.

  As America approached 1930, Oscar’s forensic tool belt was fortified: ballistics, botany, toxicology, chemistry, document analysis, and many other disciplines within the field of criminology were being developed by brilliant pioneers, including Os
car. It was also a decade of incredible growth, and there was still more to come. Blood typing, voice printing, trace blood detection using luminol, and semen tests were more than a decade away. But there were growing pains as scientists battled mistrustful detectives, skeptical prosecutors, overwhelmed juries, and undermining experts. Oscar sometimes felt he was battling a war on two fronts: first to develop the techniques in the first place, and then to bring the public and law enforcement along with him to understand and trust these new scientific advances.

  But it was a war he was winning. He didn’t triumph in every case, but slowly over many years Oscar’s reputation was being bolstered with each successful prosecution. Even better, his finances were finally stabilizing near the end of the 1920s. The period of national prosperity in Oscar’s life—and in America as a whole—seemed as though it would never end.

  But of course, all good things must end.

  * * *

  —

  The silver object came into focus, then rose up and down, blurring and clearing with every turn of his dial. He kept a notebook and a pencil nearby, stopping occasionally to record scribblings of long numbers and small drawings that only he could put into context.

  Wall bullet: 144.69 grams 0. 3546

  9.3760 grams 9.01mm

  After several minutes Oscar settled on the appropriate magnification. His eyes widened at the simple design on a single bullet pulled from a wall inside John McCarthy’s cottage. Oscar counted each of the ridges on the bullet, the numerous minuscule markings that he could detect only through the lens of his microscope. The tiny faded gray lines on the discharged slug were innocuous to a layman, but they would serve as a linchpin in this murder case.

  Oscar looked over his notes. Witnesses at a nearby ice plant heard a gunshot before McCarthy staggered from his home and pleaded for help. The fatal injury had been a “through-and-through,” a police phrase for when a bullet passes through a body.

  When they arrested fifty-nine-year-old Martin Colwell, he was armed with a .38-caliber, five-chambered hammerless Smith & Wesson revolver—the same caliber of gun used to shoot his former boss. Police discovered three bullets in Colwell’s coat pocket and a box of bullets in his boat. Colwell denied killing McCarthy, blaming amnesia from too much liquor.

  “I’ll get you all,” Colwell screamed to police. “Just wait until I get out of here.”

  Oscar was enamored of ballistics, and he marveled at the power of firearms. He vied to become a preeminent ballistics expert, using guides like John H. Fischer, Calvin Goddard, Charles Waite, and Philip Gravelle, a cohort who formed the Bureau of Forensic Ballistics in New York City in 1924.

  Forensic ballistics dated back to 1835, when a member of the Bow Street Runners, the precursors to Scotland Yard detectives, spotted irregularities in a bullet. Firearms in early America were custom-crafted by individual gunsmiths, so each part, including the barrel, screw, and bullet, was unique. The markings on the spent bullets were also exclusive to that specific gun, so experts could connect a weapon to the deadly bullet. They squinted through monocles at lead, searching for scratches left by the gun’s firing pin. They noted the distinct spiral marks that were engraved by the grooves cut into the interior of the rifled barrel.

  When gunmakers began to mass-produce weapons in the nineteenth century, experts turned to microscopes to spot more subtle irregularities. Weapons still left behind distinct markings—they were just more difficult to trace.

  In 1926, Oscar Heinrich was one of the first professional criminalists to use a new invention by chemist Philip Gravelle, the comparison microscope—one of the greatest contributions to the development of firearms identification. When analysts used two separate microscopes to compare a pair of bullets, they had to trust their memories as they moved back and forth. The comparison microscope allowed its user to compare two images at the same time—offering scientific precision along with credibility in court.

  Oscar hovered over a pair of Bausch & Lomb lenses equipped with two forty-eight-millimeter objectives—two microscopes with a pair of slides that were sitting side by side connected by an optical bridge. The device used mirrors and prisms to direct the light from each microscope to a common viewing area; a pair of oculars allowed the user to examine the two samples simultaneously, with a split screen. The first lens focused on the lethal bullet, the one that had passed through McCarthy’s body and then buried itself in his wall. Oscar slid a second bullet under the other lens, one that police discovered in the suspect’s coat pocket.

  Oscar pointed Colwell’s gun, the .38 revolver that likely killed McCarthy, at a barrel of paraffin wax and fired once. A bullet exploded from the gun, embedding into the wax. Oscar waited. Soon he carefully cut it from the thick material and soaked it in gasoline to dissolve the paraffin. Now the bullet found in Colwell’s coat would show the gun’s unique markings. If the size, shape, and direction of the twist of the grooves from both bullets matched, Colwell would likely be convicted solely based on forensics—case closed, Oscar thought. But even he should have realized that many of his cases never closed that easily. Oscar believed that this investigation would hinge on the scoring of the ridges, also called rifling marks, on the deadly bullet.

  “These ridges,” Oscar explained, “make their imprint on any projectile as clearly as a finger can leave its print.

  “The raised ridges were called ‘lands,’” he explained, “while the pattern’s shallow, small depressions were labeled ‘grooves.’”

  Investigators stared at him, clearly confused. Time to change tactics. Oscar imagined they were his college students, naïve about most things inside a lab.

  “The riflings are made by the cutting edge of a steel bar that is shoved in and pulled out of a barrel many times—fifty times in some cases and as many as a hundred in others,” he explained. “The process leaves the bottom of the grooves serrated, so that no two such marks are alike.”

  The detectives seemed to understand then, sort of. But they certainly were pleased with one bit of good news. The “bullet fingerprints,” as Oscar called them, were conclusive—Martin Colwell used his gun to kill John McCarthy.

  As Oscar sat alone in his lab, he grew uneasy. The detectives seemed dazed, just like the jury in Fatty Arbuckle’s case. His testimony might have been too technical once again, a complaint that jurors repeated throughout his career. In fact, just a few months earlier, another jury had acquitted a murder suspect despite Oscar’s conclusive ballistics evidence. The panel in that case was addled by his exhaustive explanation of rifling marks. He hadn’t learned—once again he had touted his scientific pedigree at the expense of clarity . . . and lost the case.

  He refused to allow another killer to escape prison, so Oscar prepared very differently for this trial; he was determined to show the jury why he could prove that Martin Colwell was a murderer—he just had to find a way. And then he had an idea.

  In his lab, the forensic scientist hauled his favorite camera to his desk, a Zeiss Ikon Prontor, and pointed it at the comparison microscope’s dual optics.

  “Caught image on ground glass in focus circa 140mm,” he wrote in pen. “Adjusted for center by looking through lens from rear, sighting on crosshairs on focusing glass.”

  It was so simple. With a few snaps of his shutter Oscar Heinrich shaped the future of forensic ballistics by pioneering a technique that would solve decades worth of cases.

  * * *

  —

  The courtroom was overfilled when the bailiff cautioned spectators to stay quiet; the judge leaned over his desk as Oscar sat in the witness chair and explained how he used nearly invisible ridges and grooves to catch a killer.

  “There were four panels on this bullet which were undamaged and sufficiently clear to examine microscopically,” he told the jury. “These four panels proved to be in every detail similar with the four corresponding panels on the test bullet under ex
amination.”

  Oscar pulled out from a folder a black-and-white photograph showing two bullets, side by side and separated by a thin black line.

  “I then proceeded to make a photomicrograph of what I found with the same instrument just as the eye saw it.”

  The assistant district attorney noticed jurors with quizzical looks. “What is that, professor?”

  Oscar ignored the silly job title reference and continued. “A photomicrograph is an enlarged picture made by substituting the microscope for the ordinary photographic lens and making a picture through the microscope with a combination of magnifying lenses,” Oscar replied. “If I might have a blackboard I would like to explain this more thoroughly.”

  Oscar stood up and handed copies of the photo to both sets of attorneys along with the jury before walking over to a portable blackboard. He drew a circle with chalk and sketched a diagram. Oscar hoped to offer the jury a simple explanation for how this new technique worked.

  “The photographic print shows a circle. Across this circle is a black line. That is the dividing line between the two microscopes,” he said. “I have two microscopes hitched together and I am looking at two bullets.”

  He interpreted forensic ballistics, the importance of those tiny, crucial markings left on the pair of bullets.

  “Now, in the gun there is a series of runners within the barrel, evenly placed apart, these runners have made grooves on the bullet,” he said. “There are five grooves and then five high points on the bullets between the grooves.”

  Oscar showed the jury how the grooves on the test bullet from Colwell’s pocket matched the grooves on the lethal bullet dug out of McCarthy’s wall, the one that went through his body.