His affect was disturbingly flat. I'd have trusted him more if he'd been furious with Jay, or the legal system, or nervous and thrilled at the chance to get his side of the story out.
On the podcast they briefly address this. It's chalked up to 15 years of being institutionalized.
But let's consider admins perspective. He says he didn't kill or have anything to do with the murder. Is this is his reality, then hjay killed the woman that he still loved. Remember adnan tells the nurse some stuff about how he and hae were gonna get back together after hae is found dead.
And then after participating in her death and hiding her murder, Jay pins it on him. And his only response is "well I didn't want to do the same thing to Jay that he did to me? I dunno why he is saying stuff".
If it were just a miscarriage of justice, I could understand him losing that personal anger against the larger system. But this is the guy who murders someone you were incredibly close with and by all accounts he never says anything to the guy or about that guy except "you suck"??
Prisoners dilemma!