 When the plot failed Garnet went into hiding , but he was eventually arrested on 27 January 1606 . He was taken to London and interrogated by the Privy Council , whose members included John Popham , Edward Coke and Robert Cecil , 1st Earl of Salisbury . Imprisoned in the Tower of London , his conversations with fellow prisoner Edward Oldcorne were monitored by eavesdroppers , and his letters to friends such as Anne Vaux were intercepted . His guilt , announced at the end of his trial on 28 March 1606 , was a foregone conclusion . Criticised for his use of equivocation , which Coke called " open and broad lying and forswearing " , and attacked for not warning the authorities of what Catesby planned , he was sentenced to be hanged , drawn and quartered . He was executed on 3 May 1606 . 
