=Reason for murder=

Phoenix:
You didn't just brain a guy
with a juice bottle for no
reason.

Phoenix:
Tell me why you did it.

Kristoph:
...Persistent, aren't you?

Phoenix:
I came here... because I
remembered something.

Phoenix:
The night of our "game"...

Phoenix:
...Zak Gramarye mentioned your
name, Gavin.

Zak:
Ah, that reminds me...

Zak:
I saw a familiar face as I
entered this restaurant.

Zak:
...He did not seem to
notice me, however.

Phoenix:
...?

Zak:
Gavin... I believe was his
name.

Phoenix:
...After that, he was killed.
And I asked you to help me.

Phoenix:
...Because I remembered your
kindness back when everyone
had turned on me.

...I seem to be in a bit
of trouble.

Something like that.

...Dead. Someone hit him.
Hard.

Me? Please. The cops should
be here any minute.

I'm in your hands...
Should it come to that.

Phoenix:
...I have to know.

Phoenix:
Why did you kill Shadi Smith?
No... Zak Gramarye!?

Kristoph:
......

*FIVE BLACK PSYCHE-LOCKS*

Phoenix:
(Wh-Whoa! I've never seen
Psyche-Locks like these!)

Phoenix:
(Dark... Cold...
Full of despair...)

Phoenix:
(Can I even unlock these
things...?)

Kristoph:
Something wrong, Wright?

Phoenix:
...No.
It's nothing.

Kristoph:
You shouldn't push yourself
so hard. Life is to be taken
easy, you know.

Kristoph:
......

Phoenix:
(...He's doing his nails.)

I suppose it means that he was afraid of the truth, after all, he did keep watch over everyone involved with that final case. While I'm not familiar with the information of the Black Locks, haven't played the game, after all I remember reading somewhere that Pearl explained that the locks were essentially harder to break and if broken could break a person; in other words, people either don't want to know the truth or believe their own lies(in the case of Kristoph)
It probably says a little about Kristoph's character...it can say many things, he was the coward that back stabbed two men (one who didn't really do anything and the other who was just...himself, I guess), would have killed a child (and her father) just to cover his tracks, a liar who was planning to cheat against his own brother, and probably would have sent an innocent man to jail with his fake evidence, just because he wanted fame and glory.
I don't really think black psycho locks would be able to tell us anymore than that.

It doesn't really change much about Kristoph for me other than reinforce that he really was insane in the end. I don't remember where on tumblr, but there was someone discussing the spoiler who said that there are some people who subconsciously believe their lies to be truth. I think it could mean that he won't accept his lies as what they are, lies, and believe himself to be right.

This, and the new knowledge about Black Psychelocks do fit, and we could take Kristoph as an example for those who have been completely broken by unlocking the locks (although it was his anger at Wright and the Jurist system that made him lose sanity though).

The black psyche-locks occur when the person keeps a secret unconsciously/against their will. So it isn't just that Kristoph really doesn't want to tell Nick--psychologically, he has no choice.

Also, note what the psyche-locks were about. It wasn't about if Kristoph committed the crimes--it was why. I think there are two possible ways to interpret this. The reason he killed Zak was a part of the cover-up of his forgery, which in turn was to make sure he won the case and got fame and so on. So he could have repressed that stuff, but... that seems a bit unlikely to me. Alternatively, it could be why he resorted to all that stuff in the first place. And if he himself doesn't even know why he did it, then... hmm...

Personally the way I see it is that black psyche locks are kind of an anomaly of psyche locks and there could be more than one reason for them. I have yet to play DD since I can't read Japanese but Pearl's explanation seems to me just like one of many. Who's to say Kurain village knows everything about black psyche locks? They seem way too out of the norm to have one concrete explanation. In Kristoph's case I think they just mean that they are a secret that he will absolutely never reveal because the guy is just a psycho path with no remorse and emotion. Remember even after all the evidence and logic connecting the facts and evidence together that Apollo threw at Kristoph in the trial he still refused to admit to anything and even when he learned of the jurist system and how Wright is behind it and when the verdict came in, he still didn't admit to anything. Phoenix said it best: cold and full of despair that can't be broken. Or heck maybe the locks just represent what Kristoph is on the inside. Completely devoid of any feelings or conscience and nothing will ever get him to change. He's just too stubborn to ever tell what his motives were

Lack of emotions or feelings? I think you misinterpret what a psychopath is.

He clearly does have those - perfect example being anger and jealousy.

And... Let's say it. If Pearls hadn't known exactly what they mean, she wouldn't have been so sure about them to give a proper definition. We did receive a canon explanation on the locks. Throwing it through the window is totally useless thing to do.

Lennyoh, you basically didn't say anything new. This theory basically works the same way it did in AJ:AA and you hardly said anything about it in light of the new information DD gave us. Which was the point of this thread.

I may have used the term psychopath a bit too liberally. I meant when I say he's a psychopath that he's someone who is completely cold hearted and would kill someone because he has nothing better to do that night. It's just a habit of mine to use terms too freely when I talk.

But in regards to the black psyche locks I'm not throwing the Dual Destinies explanation away entirely. I fully accept that particular explanation for Athena but when you apply it to Kristoph it doesn't fit so well. I don't know Pearl's exact words when explaining it but from what I gathered it seems the writers just had Athena's locks in mind and forgot all about Kristoph in which case we just chalk it up to bad writing for not considering Kristoph's case. My entire point is that black psyche locks may not have one single explanation. The Kurain explanation is certainly a valid one but it seems to me there's more to it than that when you consider Kristoph.

It seems to me like they may result from each individual's messed up psyche. For Athena it's her emotional trauma that's repressing her memory and for Kristoph it could be for another different reason that has nothing to do with psychological repression. Maybe the dude is just really tight lipped. Maybe it was his pure hatred for Phoenix, someone he feels is far inferior to himself, that caused the locks to appear when asked why he killed Zak. I don't know. I have to play the game myself, see the explanation and how it applies to Athena and what happens to her when they do break so I have something to compare to Kristoph.

Right now I just don't buy Dual Destinies reason for black psyche locks as the only one when I take Kristoph into consideration. It still seems too open for interpretation to me as I see it now. But then again I am basing my understanding solely off of what others say and with no solid understanding of what Athena's psyche and secret is like when it comes to her locks. So you could just consider everything I say as hearsay and dismiss my ramblings.

If black psyche locks have multiple explanations, why would Pearl only tell Nick one? How would she know which one applied to Athena?