he second type of evidence used to convict Sacco and Vanzetti was referred to by Judge Thayer as evidence of consciousness of guilt. It involved three major questions relating to their conduct during and after their arrest. First, the prosecution argued that the explanations they gave for their presence in West Bridgewater both on the night of their arrest and during their trial were false and thus at the very least tended to undermine their credibility. Second, the prosecution alleged that they had both attempted to draw their guns on the way to the police station when they were arrested on the night of 5 May. Last, the prosecution alleged that they had told many lies in their statements to Katzmann on 6 May, including some lies related to the South Braintree crime. Judge Thayer, both in his charge to the jury and in his subsequent denial of some defense motions for a new trial, laid great stress on the evidence of consciousness of guilt. From a legal standpoint, new evidence regarding the defendants' actions and statements at the time of their arrest tends deeply to undermine this part of the prosecution's case. From a historical standpoint, the whole issue of consciousness of guilt raises the question of the actual motives, activities, and character of the two defendants.
When Sacco and Vanzetti took the stand in their own defense, Katzmann devoted a large portion of his very lengthy cross-examination to various lies that he claimed they had told him during interrogations on 6 May, the day after their arrest. Legally, such lies had a dual significance: they tended to impeach the defendants' credibility as witnesses upon their own behalf, and if any of them related directly to the crime for which they were charged, they would constitute evidence of consciousness of guilt. Katzmann took particular care to establish that the defendants told lies relating to the South Braintree crime. In so doing, he read from purported transcripts of his May interrogations of the defendants—transcripts he declined to introduce in evidence. The state police files contain transcripts of Sacco and Vanzetti's answers to his questions, and the grand jury transcript also indicates some of what they actually said. These transcripts differ from the statements Katzmann read at the trial in several crucial respects.
Vanzetti, to begin with, had told Katzmann that he had bought his revolver in the North End of Boston several years previously for eighteen