The American trial, as a method of resolving disputes, determining guilt, and rendering justice, is one of our most sacred institutions. Certain rules, such as the one that prohibits witnesses from stating opinions, are designed to screen out unreliable evidence. The opinion rule, however, had this exception: qualified experts in certain scientific fields are allowed to present their informed opinions to the jury. Beginning in the mid-nineteenth century, physicians were allowed to state their medical opinions in court. Since then, the courts have been slow to accept the opinions of other experts, and to recognize other sciences. The courts will not allow, for example, the testimony of polygraph examiners, hypnotists, and graphologists. During the first two decades of the twentieth century, the courts began to recognize a group of disciplines related directly to criminal investigation. Now called criminalistics, these sciences include fingerprints, questioned documents, and firearms identification. During this crucial period, the future of criminalistics was threatened by phony experts. Perhaps the most serious threat involved one of the era's most famous personalities, the star witness in the Sacco-Vanzetti defense, and a key player in dozens of celebrated cases. This man was Albert Hamilton, and, as it turned out, he was the biggest phony of them all. He was America's greatest courtroom charlatan. In 1908, Hamilton published a brochure about himself called, “That Man From Auburn.” In this piece of self-advertisement, the druggist from Auburn, New York described himself as an expert in chemistry, microscopy, handwriting, ink analysis, typewriting identification, photography, fingerprints, and forensic toxicology. He also claimed expertise in the fields of gunshot wounds, bullet identification, guns, nitroglycerine, gun powder, blood stains, causes of death, anatomy, and embalming. To match his impressive qualifications, he awarded himself a medical degree, and from then on he was known as Doctor Hamilton. Albert Hamilton came into prominence in 1915 when he testified for the prosecution as a firearms expert in a rural New York murder case. The defendant was Charlie Stielow, a slightly retarded farm hand who was accused of shooting to death the couple who owned the farm where he worked and lived. Stielow was convicted of first-degree murder on the strength of a coerced confession and the ballistic findings of Hamilton who testified that a scratch inside the barrel of Stielow’s 22 caliber revolver had made a mark on one of the murder bullets. Having earned fifty dollars a day for his work on the case, Hamilton impressed the jury by showing them enlarged photographs of the fatal bullet. Hamilton's testimony was pure hokum. The science of firearms identification as it is practiced today, did not exist in 1915. The comparison microscope, an instrument essential to the comparison and analysis of firearms evidence, was not invented until 1926. Nevertheless, Hamilton assured the jury that the fatal bullet had been fired from the defendant's gun. His findings went unchallenged, and no one seemed to notice that he hadn't even test-fired the so-called murder weapon. Charlie Stielow was found guilty, and sentenced to death. Two years later, a pair of tramps confessed to the murder, and the Governor of New York formed a commission to review the case. Charles Waite, an investigator in the New York Attorney General's Office, was appointed by the commission to look into the matter. Waite took Stielow's revolver to a New York City police detective who knew firearms. A thorough examination of the gun convinced the officer that Stielow's revolver hadn't been fired in four years. Moreover, a naked eye examination of the test-bullets showed vastly different barrel marks than those found on the murder bullets. As a result of these findings, Charlie Stielow was pardoned, and Charles Waite went on to become a well-known firearms expert. In 1922, Waite formed the Bureau of Forensic Ballistics in New York City. The bureau, the first of its kind, was taken over in 1926 by Dr. Calvin Goddard an Army surgeon and ordnance officer from Baltimore who became the most prominent firearms identification expert in the world. In 1923, two Italian-American anarchists, Nicola Sacco and Bartolomeo Vanzetti, were convicted of shooting a factory paymaster and his bodyguard to death in South Braintree, Massachusetts. The defendants' attorneys were seeking grounds for a new trial and called upon the services of Albert Hamilton. Since the Sacco-Vanzetti case had been grabbing headline for months, Hamilton eagerly got involved in the case. Sacco's conviction has been based chiefly on the testimony of three firearms witnesses who said the bullet that killed the guard had been fired from his 32 caliber handgun. The experts also believed that the gun the police found on Vanzetti when they arrested him had belonged to the slain guard. After examining the firearms evidence, Hamilton reported that the fatal bullet had not been fired from Sacco's gun, and the weapon in Vanzetti's possession was not the gun that belonged to the bodyguard. Relying on Hamilton's findings, the Sacco-Vanzetti defense made a motion for a new trial. To counter this motion, the prosecution acquired the services of two new experts. In November, 1933, during the hearing for the new trial, Hamilton conducted an in-court demonstration involving two Colts and Sacco's gun. The new 32 caliber handguns belonged to Hamilton. In front of the judge and the lawyers for both sides, Hamilton disassembled all three pistols and placed their parts in three piles on the table. He then explained the functions of each part and demonstrated how they were interchangeable. After reassembling the handguns, Hamilton placed the two new weapons back into his pocket and handed Sacco's Colt to the court clerk. Before he left the courtroom, the judge asked Hamilton to leave the new guns behind. Several months later, when the judge asked one of the prosecution firearms experts to reinspect Sacco's gun, the expert discovered that the barrel to Sacco's gun was brand new. Following an inquiry, Hamilton admitted that the new barrel on Sacco's Colt had come from one of his pistols. Although it was obvious to everyone that Hamilton had made the switch, presumably with a mistrial in mind, he denied it. Hamilton continued his association with the Sacco-Vanzetti defense, but he no longer played an important role in the case. He had destroyed his credibility as a firearms expert witness. The Sacco-Vanzetti motion for a new trial was denied, and in 1927 the two men were executed. Prior to their death, Dr. Calvin Goddard, the most qualified firearms examiner in the world, stated that Sacco's gun had been the murder weapon. (Several modern firearms experts have examined the ballistics evidence in the case and agree with Goddard's findings.)