The trial of Sacco and Vanzetti was the 1921 Massachusetts prosecution of two Italian immigrant anarchists, Nicola Sacco and Bartolomeo Vanzetti, for a payroll robbery and double murder in South Braintree. Both men were convicted, both were executed on August 23, 1927, and fifty years later the Commonwealth of Massachusetts formally acknowledged that they had not received a fair trial. Whether they actually committed the crime is still contested. That their trial was shaped by anti-immigrant prejudice, a hostile judge, and manipulated expert testimony is not.
The South Braintree Payroll Murders
On April 15, 1920, paymaster Frederick Parmenter and security guard Alessandro Berardelli were carrying a $15,776.51 payroll from the executive office of the Slater and Morrill shoe factory to the main factory building in South Braintree. Two armed men attacked them on the street. Berardelli was shot four times and died at the scene. Parmenter was shot twice and died the next day.1Mass.gov. Sacco and Vanzetti: The Crime Scene The gunmen loaded the payroll into a dark touring car with accomplices and drove off. Witnesses gave conflicting descriptions but generally agreed the shooters looked Italian.
Local police chief Michael Stewart tied South Braintree to an earlier failed payroll robbery in Bridgewater on December 24, 1919, and ran both investigations on the theory that a single group was responsible.2Mass.gov. Sacco and Vanzetti: The Trial
How Sacco and Vanzetti Became Suspects
Police set a trap at a garage where a car linked to the Bridgewater case was being kept. On the evening of May 5, 1920, four Italian men came to retrieve it. The garage owner’s wife called police. Later that night, officers arrested Sacco and Vanzetti on a streetcar in Brockton. Sacco was carrying a loaded .32 Colt automatic; Vanzetti had a loaded .38 Harrington and Richardson revolver.3Mass.gov. Sacco and Vanzetti: Investigation and Arrest
Neither man had been a suspect in the South Braintree killings before that night. When questioned, both lied. They denied knowing the other men at the garage and denied their ties to anarchist circles. The prosecution would treat those lies as consciousness of guilt. Sacco and Vanzetti said they had believed they were being arrested for their politics. Vanzetti testified that police asked him whether he was a Socialist, an Industrial Workers of the World member, a Communist, or a Radical, and that no one told him he was suspected of robbery or murder.4Mass.gov. Sacco and Vanzetti: The Evidence Federal agents were arresting and deporting radicals by the thousands under Attorney General A. Mitchell Palmer at that time.5Federal Bureau of Investigation. Palmer Raids
Before South Braintree ever reached a jury, Vanzetti was tried separately for the Bridgewater attempt. Judge Webster Thayer presided. Sacco was not charged because his employer’s records placed him at work that day. The jury convicted Vanzetti, and Thayer sentenced him to 12 to 15 years.2Mass.gov. Sacco and Vanzetti: The Trial He entered the murder trial as a convicted felon, and the same judge would preside there too.
The Prosecution’s Case at Dedham
The murder trial began in Dedham on May 31, 1921. The prosecution rested on three things: ballistics, eyewitness identifications, and the defendants’ lies at arrest.
The ballistics case turned on a single bullet. The prosecution argued that “Bullet III,” recovered from Berardelli’s body, had been fired from Sacco’s .32 Colt. State Police Captain William Proctor testified the bullet was “consistent with being fired” from Sacco’s gun. It sounded like an identification. It was not.4Mass.gov. Sacco and Vanzetti: The Evidence Proctor had told the district attorney before trial that he could not conclude Bullet III had actually passed through Sacco’s pistol, and the questions at trial were phrased so the jury would hear a positive identification while Proctor could technically stand by his weaker opinion.6Mass.gov. Sacco and Vanzetti: Motions for a New Trial
The prosecution also introduced a cap found at the crime scene, arguing it belonged to Sacco. A witness said it resembled his cap, and prosecutors suggested a hole in the lining came from a nail where Sacco hung it at work. Sacco tried it on for the jury and said it did not fit. The cap evidence unraveled later: during the Lowell Committee hearings it emerged that the hole had actually been made by the Braintree chief of police.7Famous Trials. Summary of Evidence in the Sacco and Vanzetti Case
Several witnesses said they had seen the defendants near the crime scene or in the getaway car. The defense pressed inconsistencies in their descriptions and the distances they had watched from.
What the Defense Put On
Sacco testified he had taken the day off on April 15, 1920, and traveled to Boston to apply for a passport at the Italian consulate. A consulate official confirmed rejecting an oversized photograph Sacco had brought, and remembered the encounter specifically because the odd photograph had prompted discussion among staff, during which he had clearly seen the date on a large office calendar.4Mass.gov. Sacco and Vanzetti: The Evidence Other witnesses also placed Sacco in Boston that day.
Vanzetti testified he had spent the day selling fish in Plymouth, roughly 25 miles from South Braintree. Several witnesses corroborated him.4Mass.gov. Sacco and Vanzetti: The Evidence Most of the alibi witnesses were Italian immigrants, and the prosecution went after their credibility on that basis.
Why the Trial’s Fairness Became the Story
The case unfolded during the First Red Scare, and both defendants were open anarchists. Their politics ran through every part of the courtroom. Jury selection itself was unusual: according to Harvard law professor Felix Frankfurter, part of the jury was specially selected by sheriff’s deputies from Masonic gatherings and from people the deputies considered “representative” and “substantial” citizens.8The Atlantic. The Case of Sacco and Vanzetti
The judge’s conduct outside the courtroom was worse. Thayer was reported to have called the defendants “anarchist bastards” and to have said he would “get them good and proper.” He complained about “no long-haired anarchist from California” running his court, a reference to defense attorney Fred Moore. A Massachusetts state account records an even more damning line attributed to Thayer: “These two men are anarchists; they are guilty… They are not getting a fair trial, but I am working it so that their counsel will think that they are.”9Mass.gov. Sacco and Vanzetti: Justice on Trial
The judge who ruled on every evidentiary question, and who would later rule on every motion for a new trial, had privately decided the defendants were guilty anarchists who deserved punishment. That is the fact that has followed the case ever since.
The Verdict and the Motions Thayer Denied
On July 14, 1921, the jury convicted both men of first-degree murder. Between 1921 and 1926, the defense filed a series of motions for a new trial. Thayer denied all of them.6Mass.gov. Sacco and Vanzetti: Motions for a New Trial
Two of those motions matter most.
The Ripley-Daly motion argued that jury foreman Walter Ripley had said before trial, “Damn them, they ought to hang anyway.” If true, the foreman had prejudged the case. Thayer denied the motion.6Mass.gov. Sacco and Vanzetti: Motions for a New Trial
The Proctor motion was worse for the prosecution. In October 1923, Captain Proctor signed an affidavit stating that his trial testimony had been engineered to mislead the jury. He swore he had never found evidence that Bullet III passed through Sacco’s pistol, that he had told the district attorney so before trial, and that the district attorney had shaped his questions to make the answer sound like a positive identification. In Proctor’s own words: “I did not intend by that answer to imply that I had found any evidence that the so-called mortal bullet had passed through this particular Colt automatic pistol and the District Attorney well knew and framed his question accordingly.”6Mass.gov. Sacco and Vanzetti: Motions for a New Trial Thayer denied that motion too.
Then, in November 1925, an inmate named Celestino Madeiros, who was awaiting appeal of his own murder conviction, sent Sacco a note in prison: “I hear by confess to being in the South Braintree shoe company crime and Sacco and Vanzetti was not in said crime.” Defense investigators traced Madeiros’s descriptions to the Morelli gang, a group of Italians in Providence and New Bedford known for robbing freight cars. Frankfurter, by then a Harvard Law professor, wrote that “every reasonable probability points away from Sacco and Vanzetti; every reasonable probability points toward the Morelli gang.”10Mass.gov. Sacco and Vanzetti: The Madeiros Confession and Felix Frankfurter Thayer denied the motion.
Under Massachusetts law at the time, only the trial judge could grant a new trial. No appellate court could order one based on the overall prejudicial character of the proceedings. The judge whose bias was the problem was the judge deciding whether the trial had been fair.
The Lowell Committee and the Executions
By 1927, protests over the case were being held in London, Paris, Milan, Berlin, and cities across South America and Asia. On June 1, 1927, Governor Alvan T. Fuller appointed an advisory committee to review the case. It was chaired by Harvard President A. Lawrence Lowell, alongside MIT President Samuel Stratton and retired probate judge Robert Grant. In August 1927, the committee concluded that the trial had been fair and that Sacco and Vanzetti were guilty beyond a reasonable doubt.11Mass.gov. Sacco and Vanzetti: The Lowell Committee Critics noted that the panel was drawn from Massachusetts establishment figures with no incentive to embarrass the state’s judiciary.
Sacco and Vanzetti were electrocuted at Charlestown State Prison on August 23, 1927. Madeiros was executed the same night for his unrelated murder conviction.12Mass.gov. Sacco and Vanzetti: The Executions and Funeral Sacco cried out “Long live anarchy” and asked that his family be cared for. Vanzetti said in broken English, “I wish to tell you I am innocent and never connected with any crime… I wish to forgive some people for what they are now doing to me.”13Digital History. Sacco and Vanzetti Put to Death Early This Morning
What Later Evidence Showed
The case did not end at the electric chair. In 1961, firearms consultants Jac Weller and Lieutenant Colonel Frank Jury retested Sacco’s pistol using modern comparison microscope technology. Both concluded independently that Bullet III had been fired from Sacco’s pistol “and in no other,” and that a spent shell casing found at the scene also matched the gun. The finding suggested the ballistics evidence against Sacco, whatever the problems with Proctor’s testimony, may have been correct.
It did not resolve the case. The chain of custody for Bullet III was never above suspicion, and critics have questioned whether the bullet or shell could have been substituted after the crime. Fred Moore, the original defense attorney, later told an acquaintance that while neither defendant had ever admitted involvement to him, he had come to believe privately in Sacco’s guilt while remaining less certain about Vanzetti.
The Dukakis Proclamation
On July 19, 1977, on the fiftieth anniversary of the executions, Massachusetts Governor Michael Dukakis issued a formal proclamation. It said “the atmosphere of their trial and appeals was permeated by prejudice against foreigners and hostility toward unorthodox political views,” that the conduct of officials “shed serious doubt on their willingness and ability to conduct the prosecution and trial of Sacco and Vanzetti fairly and impartially,” and that the appellate review available at the time “did not allow a new trial to be ordered based on the prejudicial effect of the proceedings as a whole.” Dukakis declared “that any stigma and disgrace should be forever removed from the names of Nicola Sacco and Bartolomeo Vanzetti.”14Rosa Luxemburg Stiftung (RFC). Proclamation by Gov. Michael S. Dukakis of Nicola Sacco and Bartolomeo Vanzetti Memorial Day
The proclamation did not declare them innocent. It declared that they had not received a fair trial. That distinction is why the case still gets taught. Guilt or innocence remains genuinely uncertain. The failure of the process does not. A biased judge with sole authority over new-trial motions, a prosecution that shaped its expert’s testimony to imply what the expert could not say, a jury partly hand-picked by sheriff’s deputies, and an appellate system with no way to correct any of it produced a verdict and two executions. The reforms to appellate review in Massachusetts that followed, and the broader national argument over the rights of capital defendants, trace back to what happened in Judge Thayer’s courtroom.