Escalus' role as a foil to Angelo is evident in the first few lines of Scene 1. The elder pleads the cause of mercy, but the deputy remains unmoved. Angelo is determined to make an example of Claudio by applying the letter of the law that has so long been disregarded.
Ironic foreshadowing pervades the opening conversation in Scene 1. Escalus asks Angelo to consider that had time and place ever been right, he might himself have been guilty of the crime of which Claudio stands accused. Angelo, however, argues that to contemplate a crime is one thing and to commit it another: "'Tis one thing to be tempted, Escalus, / Another thing to fall" (17-18). Angelo tells Escalus not to argue mercy for the criminal but rather to challenge him to demand the same punishment for himself should he be guilty of the same offense. The law should show no mercy, but treat each one the same: "Let mine own judgment pattern out my death" (30). Ironically, Angelo does commit (or attempt to commit) the same crime later in the play and does, in fact, ask that the full measure of the law be dealt him.
The entry of Elbow, Froth, and Pompey in Scene 1 provides comic relief to the grave discussion that opens the scene. The conversation of Elbow, the constable, is laden with malapropisms. He uses "benefactors" when he means "malefactors," declares that he "detests his wife before Heaven" when he means "protests," and calls a house of ill-repute "respected" ("suspected").
Accused of some crime against the constable's wife, Froth and Pompey carry on at length, describing the circumstances in such detail that Angelo wearies and leaves the matter to Escalus. At last, in despair of ever getting to the bottom of it, Escalus advises that Elbow allow Pompey to continue in his trade until his crime can be more certainly discovered. Warned to stay away from bawds, Froth exits. Pompey engages in a debate with Escalus on the subject of legislated morality. He concludes that sex is a markedly general crime: "If you head and hang all that offend that way but for ten year together, you'll be glad to give out a commission for more heads" (251-53). Pompey is threatened with a whipping, but he too escapes with no more than a warning.
