If the Crown Controls Prosecution ...
Since any Englishman could prosecute a criminal case, the fact that an offense was approved of by the authorities was no guarantee that it would not be prosecuted. The point was demonstrated when a demonstration in favor of imprisoned radical John Wilkes ended with troops firing into the crowd and killing several people. The Wilkites responded by charging several of the soldiers, the magistrate who had ordered the troops to fire and the other magistrates present with murder.
The king had the power to pardon a convicted felon but doing so in too obviously partisan a way might provoke public outrage. In one notorious case two convicted murderers were pardoned, apparently because their sister’s aristocratic lovers applied political pressure on their behalf (“the mercy of a chaste and pious prince extended cheerfully to a wilful murderer, because that murderer is the brother of a common prostitute”). The Wilkites responded by raising money to fund an appeal of murder, a private criminal case. An appeal was a complex, expensive and difficult proceeding that had gone almost entirely out of use. It had, however, one large advantage:
“If the appellee be found guilty, he shall suffer the same judgement as if he had been convicted by indictment: but with this remarkable difference; that on indictment, which is at the suit of the King, the King may pardon and remit the execution; on an appeal, which is the suit of a private subject, to make an atonement for a private wrong, the King can no more pardon it, than he can remit the damages recovered in an action of battery.” (Blackstone)The appeal failed, as did the earlier criminal prosecutions, but like them demonstrated the possibility of using privately prosecuted criminal law against malefactors supported by the government
When told by a constituent that he would rather vote for the devil, Wilkes responded: "Naturally." He then added: "And if your friend decides against standing, can I count on your vote?"
At one point in his extended feud with George III, Wilkes was asked to make up a table of cards. He declined, explaining that he was so ignorant of cards that he could not tell a king from a knave.
In a famous exchange with John Montagu, 4th Earl of Sandwich, where the latter exclaimed, "Sir, I do not know whether you will die on the gallows or of the pox," Wilkes is reported to have replied, "That depends, my lord, on whether I embrace your lordship's principles or your mistress." (But that one may really be by Samuel Foote)