To say the very, very, very least. :moo: it's not important to find the missing just so we have evidence that will hopefully put those responsible behind bars, we want to find them to bring them home to their families, to give them whatever measure of comfort that will give them.
I can see how MTR could rationalize not being responsible for Tori's death if he wasn't in the immediate area when TLM killed her. I can see him rationalizing not going to police to turn TLM if he was afraid for his life. Its a stretch, but I none the less can see it.
But he was causing an immense amont of pain just by keeping her whereabouts hidden. And it's not like he avoided situations where he was confronted by this pain. He talked about it with others. I'm assuming while doing so he mimicked that pain, that emotional response. And then for good measure he talked about having insider info, being close to TLM, to draw even more attention to his involvement so others would feel especially sorry for him, to increase his chances of getting laid.
He even said he was going out looking for Tori. He could have brought up Tori's disappearance for a sentence or two during conversations, that was probably closer to the norm than what he did do. He didn't have to draw attention to himself like that. But he did, and in doing so got to look at the hurt and pain Tori's disappearance was causing people over and over and over again like he enjoyed doing so.
Thats more than warped morals and ethics. :moo: