The Euthyphro, the Apology, the Crito, and the Phaedo are all situated at different points in the story of the trial and death of Socrates. But it does not follow that they are written as chapters in a single narrative. They may have been written as free-standing discussions of distinct topics, and indeed when one considers the various philosophical agendas, this also seems a reasonable approach. So if there is apparent inconsistency between the Apology and the Crito, it may be no more than a reflection of the way that they were written. We’ll probably never know.
You ask: -- “If Plato's Socrates is willing to disobey a law which says Don't philosophize, why won't he disobey the state when it comes to life and death?”
I don’t think this is inconsistent. Socrates points out several times that he does not fear death and even thinks it may be a good thing. So one assumes that he thinks that philosophy is more important than his own life. Perhaps he believes that breaking a law to pursue philosophy is worth it, but breaking it to save his own life is not. That would be a comprehensible choice.
What is less easy to understand why he does not think it worth while to save his own life so that he can pursue his mission for longer. This might be achieved by going into exile. But he is clear that he is not willing to do that. However, being unable to pursue philosophy is not one of the reasons he offers. In the Apology, at (37b – d), he considers the possibility of proposing exile as his penalty (see note at end of this answer) and seems to assume that this would not prevent him from philosophizing.
He dismisses the idea on the ground that there is no reason to propose anything “evil” since he has done nothing wrong. He thinks exile would make his life hard because he would be hounded from city to city as the local citizens got fed up with him. He never considers the point that this would enable him to continue his mission. Of course, it may be that he thinks that his mission is not merely to philosophize, but to do so at Athens, to instruct the Athenians. Exile would prevent that.
In the Crito, the die is cast. There still remains a way out – to escape prison and flee the city, and this is what Crito is urging Socrates to do. His decision not to accept Crito’s offer is no surprise, since he rejected exile in the Apology. But the reason he gives for rejecting it is different. He agrees with Crito that it is wrong to return wrong for wrong. So the fact that the verdict is wrong, is no excuse for breaking the law. His duty to the law is explained as an “agreement” – in effect, a contract – which is established by anyone who stays in the city after he has seen how the laws govern the state and dispense justice. Disobedience is wrong in three ways; the laws parented him from childhood, they have taken care of him and he has chosen to stay in Athens.
The laws themselves explain why escaping illegally would not be worth it, including why it would not be possible to fulfil his mission.
. . all who care for their own cities will look askance at you, and will
consider you a destroyer of the laws, and you will confirm the judges in
their opinion, so that they will think their verdict was just. For he who
is destroyer of the laws might certainly be regarded as a destroyer of young
and thoughtless men. . . Or will you go to them and have the face to carry
on — what kind of conversation, Socrates? The same kind you carried on here, > saying that virtue and justice and lawful things and the laws are the most
precious things to men? And do you not think that the conduct of Socrates
would seem most disgraceful?” (53b – d)
I see difference between the dialogues, and a variety of different explanations rather than a single consistent case, but not inconsistency. It might be possible to work out what’s going on. (For example, Plato might be providing the most appropriate of the available explanations for the specific context at stage of the argument.) But I think that would not be necessary to answer the question.
- Note on sentences after guilty verdicts in the Athenian system
Athenian practice was that when someone is found guilty of a crime, prosecutor and defendant are each required to propose a penalty. The jury had a binary vote for one or the other. Naturally, the prosecution will propose the most severe penalty that he thinks might be imposed and the defence will propose the most lenient penalty that he thinks he might get away with.