In the early part of the seventeenth century Parliament remained, in the words of Conrad Russell,‘an event and not an institution’. 1 Indeed, over the course of the twenty-two years of James I’s reign, Parliament was in session for only about thirty-six months. During the rest of the period James ruled according to his prerogative, the general term applied to royal discretionary powers. However, the ill-defined nature of these royal rights and privileges led to disagreements in each of James’s Parliaments.