Griswold had a long trial. He took a change of venue from Denver to Evans, Weld county, and there, after the case was thoroughly tried, he was remanded to jail in Denver for a new trial. Eleven of the jurymen favored hanging, and the twelfth was for bringing in a verdict of manslaughter and sending him to the penitentiary for life. No one doubted the man's guilt. The splendid chain of evidence which Gen. Cook had prepared left no room for doubt on that score. But the twelfth man was not a believer in hanging and held out to the last, causing the jury to go before the court with a disagreement report. The murder of O'Neal had been committed on the 10th of July, 1870, but, owing to delays, the month of February, 1872, had now come around, and the law was only preparing to take its course. Griswold, who had been the cause of so much summary punishment, looked forward to his own fate with the greatest dread, and began to make preparations to escape. His plans were well laid, and as he had plenty of outside assistance, it is a great wonder that he did not accomplish his purpose. He was certainly desperate enough, as will soon appear.
It was on Saturday, the 24th of February, that an attempt was made to escape from the county jail in Denver, and which attempt resulted in one of the most exciting scenes ever witnessed in a prison. Two prisoners, Michael Henesee and a negro, named Dan Diamond, were engaged scrubbing the premises and making a general clean-up. While in the companion way leading between the cells from the front office to a room adjoining the day cell in the rear, they had occasion to wash the cells of Griswold and E. E. Wight, the last named being the man who figures in the Wall murder story. The turnkey, Sanford W. Davis, allowed these men to emerge from their cells for the purpose of going to the water closet, a few feet away, and in the enclosure, there being no accommodations for them in the cells, and as both were heavily ironed no fears were entertained of any outbreak. Griswold passed to the front office and called out to L. F. or "Till" Davis, brother to the turnkey, for a chew of tobacco. Davis was in the bedroom adjoining and did not answer, whereupon Griswold turned back, and as he did so he suddenly drew a bludgeon, consisting of a boulder in the toe of a stocking prepared in the water closet, from some place of concealment and dealt the turnkey a blow on the back of the head. This had the effect to fell him to the floor, but he soon regained his feet, and after a scuffle with Wight, Griswold and Diamond, the negro, who had joined the mutineers, he ran towards the large room in the rear, closely followed by Griswold.