How did the trial of the three Indians violate the spirit of the Mayflower Compact?

Philbrick places the trial of the three Indians in the context of the rapidly deteriorating relations between the Pilgrim settlers and the Native American tribes they encountered. The first generation of settlers had established generally good relations with the Native American tribes, despite the occasional setback. However, the second generation of settlers, having no memory of the difficult early years, had become, in the words of the Pilgrim leader William Bradford, "the ruin of New England” due to their insatiable hunger for land.
Inevitably, this led to a bitter conflict with the Native Americans, whose land the new generation of settlers was now busily stealing. Tensions culminated in the murder of a Christian Indian by the name of John Sassamon, which resulted in the arrest of three Native Americans. Their subsequent treatment at the hands of the Plymouth authorities represented a clear violation of the Mayflower Compact and the principles on which it was based. The Compact pledged the Pilgrim Fathers to establish government on the basis of the rule of law. Yet in the case of the three Indians, the accused were tried, convicted, and executed without the slightest evidence of their guilt. Their executions were an act of revenge and had nothing whatsoever to do with upholding the law as the original Pilgrim settlers aboard the Mayflower had pledged to do.