Crito has given Socrates a number of reasons why he should leave Athens. In 48b-c, Socrates has dismissed these considerations. He says that the key question is whether or not, based on the principles he and Crito have agreed to in previous discussions, it would be right for him to leave Athens against the will of the Athenians. οὐκοῦν ἐκ τῶν ὁμολογουμένων τοῦτο σκεπτέον, πότερον δίκαιον ἐμὲ ἐνθένδε πειρᾶσθαι ἐξιέναι μὴ ἀφιέντων Ἀθηναίων ἢ οὐ δίκαιον. 48d.
Socrates goes on to say that Crito’s proposals shouldn’t even be considered if it would be wrongful to do what Crito wants him to do and leave Athens, even if it means he will die by staying and doing nothing, or even if he will undergo anything else instead of doing something that is wrong. κἂν φαινώμεθα ἄδικα αὐτὰ ἐργαζόμενοι, μὴ οὐ δέῃ ὑπολογίζεσθαι οὔτ᾽ εἰ ἀποθνῄσκειν δεῖ παραμένοντας καὶ ἡσυχίαν ἄγοντας, οὔτε ἄλλο ὁτιοῦν πάσχειν πρὸ τοῦ ἀδικεῖν. 48d.
Socrates goes on to lead Crito through his argument, beginning with the principle that no one should ever under any circumstances do wrong, pointing out that Crito has agreed with this. Socrates frames this as a question: οὐδενὶ τρόπῳ φαμὲν ἑκόντας ἀδικητέον εἶναι, ἢ τινὶ μὲν ἀδικητέον τρόπῳ τινὶ δὲ οὔ; “Do we agree that in no way should we willingly do wrong? or might we do wrong in some way but not in another?” Plato uses the verbal adjective ἀδικητέον in the second question to mean something like “might our ethical obligations, while permitting us to do wrong in some way, prohibit us from doing wrong in another?”
He then reframes the question: ἢ οὐδαμῶς τό γε ἀδικεῖν οὔτε ἀγαθὸν οὔτε καλόν, ὡς πολλάκις ἡμῖν καὶ ἐν τῷ ἔμπροσθεν χρόνῳ ὡμολογήθη; Or is wrongdoing never good or noble, as we’ve agreed many times previously?
Crito concedes that they’ve agreed we should never do wrong in 49b, when he says φαμέν, in response to Socrates’ φαμὲν; in 49a and again in 49b more insistently, φαμὲν ἢ οὔ; “Do we agree?” “Yes, we agree.”
Then Socrates goes on to explain that doing wrong in response to a wrong is wrong, and why it would be a wrongful act to leave Athens against the will of the Athenians.
Maybe it would be helpful to read at least this portion of the Crito in an English translation to get a sense of how the dialogue develops.