Final answer:
English kings were considered tyrants for abusing power, such as imposing taxes without consent and denying trial by jury, as critiqued in the Declaration of Independence and exemplified by the reign of King Charles I.
Step-by-step explanation:
English kings were labeled tyrants when they abused power. This abuse of power was evident in actions such as taxing the colonists without their consent, interfering with trade, denying the right to trial by jury, and depriving them of the right to self-government. Historical documents such as the Declaration of Independence criticize the tyranny of King George III, who was seen as abusing his 'tyrannical power'. Furthermore, the reign of King Charles I was marked by his failure to work with Parliaments, leading to fiscal chaos and the perception of tyranny, eventually culminating in the English Civil War.