Besides, Phoenix didn't give him the evidence directly. If Apollo, too, is dumb enough to take random 'evidence' from a strange girl he's never met, and then present it in court (Phoenix's real 'crime') then I suppose jaded Phoenix reasons Apollo should fend for himself. It wouldn't have ended as badly as the Zak thing, since Phoenix claims the card as his upon presentation (so would have taken responsibility) but it's lacking integrity from an 'Apollo's Mentor' perspective.

Now, this kind of Apollo abuse actually gives me the opposite impression . It doesn't mark Phoenix as someone 'fallen' from ever being a lawyer - but as someone who only played a terrible role as 'mentor' to Apollo. Phoenix was a spectacularly bad 'mentor', who exploited Apollo in all kinds of unethical ways. Having him hang around in any kind of non-lawyer 'mentor' capacity to Apollo, even in a reduced format, is a terrible idea as 'Apollo's Mentor' is the role Phoenix has proven himself as too corrupted and lacking integrity to ever hold again, not 'Lawyer.' And I can't see Phoenix ever playing a positive mentor role unless he's also a lawyer, there'd be too many regrets and 'living through Apollo' clouding his judgment. (We all know Mia was living on through Phoenix. - but she really was dead.)

If Phoenix himself had thought his 'sacrificed integrity' to catch Kristoph also sacrificed his intentions to be a lawyer again, he just wouldn't have ever made that comment in the credits 'Maybe I'll take the Bar Exam.. again".

As for 'facing consequences' well, he did. He told Apollo, Apollo punched him, and that was that. If the justice system had caught on, it's Phoenix who would have suffered anyway - he's the one who would have been charged with murder. Besides, unlike Zak, he claimed the card as his when it was presented. Phoenix wasn't a lawyer, and there's nothing to say he believed in any 'client-lawyer relationship' from the client end which he was somehow breaching either. He was a terrible defendant for Mia in 3-1 as well, after all. And on his part, he had some pretty unhelpful clients (Iris and of course Zak spring to mind.) Phoenix's role in that trial was defendant, not lawyer, and there was no requirement to constrain himself to his lawyer ethics or assume he was permanently sacrificing his lawyer integrity.

He's obviously cast as a character who's playing with a system which he considered broken, forced in so they could have some kind of weight behind the 'jurist system' thing (I didn't think this was very effective, and doubt it would have converted me to the wonders of jurist systems had I not already had general acceptance of them due to their being a standard Western law concept)

In fact he plays with and manipulates the 'game' on a higher level/4th wall, which I suppose is the equivalent of Mia's spiritual dimension powers, except since we don't have some reasoning/concept to make this seem plausible, it's just weird and confusing. But if they do implement jurist systems, (that's left ambiguous too) there's even less reason to suspect he'd repeat that kind of behaviour or attitude, since things have changed so it's no longer such a broken system which he's lost respect for.

I suppose Phoenix favouring corrupting himself permanently in pursuit of Kristoph over ever being a lawyer again is a possible take on Hobo Phoenix in peoples' imagination, (not to mention the whole Phoenix/Kristoph thing) but there's not much to suggest it's the main interpretation in the writers' minds or the one they would pursue with his character in future games if they were made. Besides, it's of no use to Apollo to have a jaded hobo mentor for another game. It served its purpose in the story in supposedly trying to convince us the legal system needed reform, and has more than run its course in terms of plot usefulness.

People forget the connotations of being a defendant, rather than a lawyer or bystander 3rd party. What happens if Phoenix is found guilty? Probably the death penalty. The stakes are just totally different. Would you bend a few rules to save your own life, if the only one who was likely to suffer was the real murderer? Most people would. And letting Kristoph pin the murder on Orly would be far more unethical than the card thing, even if Phoenix himself wasn't 'breaking any rules' by allowing it to occur.

Phoenix's rule breaking, corruption and general disenfranchisement seem to stem from:
-a lack of empowerment to carry out his goals by legal means any more, due to the loss of his badge, which was a total injustice
-a disenfranchisement with the legal system generally, which he now considers broken, to bring up the jury thing (although I'm not sure they did a very good job in conveying this or exactly what was supposed to be wrong with it.)

As you can see, the end of 4-4 'corrects' both these. I don't get the sense Phoenix wants to achieve his goals by breaking rules, forging evidence and exploiting Apollo; he simply feels he has no choice in that situation since the loss of his badge. I also think Phoenix was enough of a rule-bending deviant even by the original series to not think his evidence forgery, taken in proper context, renders him morally unfit to ever be a lawyer again. He shows obvious regret and shame over it (witness punching scene) but I think he'll see it as the best of a number of questionable choices in a very bad situation, and move on. If he can achieve his justice goals without breaking rules (having the empowerment to be a lawyer himself instead of forging evidence and hijacking 'Apollo's' defense) I'm sure he would prefer to do so.