There's a helplessness in here that causes people to do things they would never consider. Helplessness, helplessness.
The words he told Rossi just hours earlier swam around his brain as he sat trapped in his cell, chaos rumbling around him like a distant thunderstorm, ready to strike him. A PhD in chemistry can get you out of many sticky situations, but when switching out the cocaine for bleach powder, Spencer never thought so many people would end up affected. Even his only 'friend' in the place, Shaw, was currently being rushed to medical, and there was very little chance he would come back. The idea was for the batch to be checked, for them to realise it was faulty, assume that they couldn't trust Reid around the drugs, and not have him move them anymore. He figured with Shaw's protection no one would kill him for it. But now he was high on coke, trapped like a rat, whilst innocent people died because of his own desperation. A helplessness so all-encompassing he didn't stop to think about the rest of the inmates, he didn't consider all the possible outcomes, something he prided himself on in his line of work.
As a profiler, he ended up in more than one sticky situation, yet he always had an answer, a way out. When he was kidnapped by Tobias Hankel he had a plan, no matter how much dilaudid entered his system and clouded his judgement, he had a way out. When he was in the restaurant with Kat, with a gun pointed at him, and most of his backup sent away, he had a way out. But now, in a prison, the only way to clear his name to prove someone set him up, but he couldn't even remember enough to know for sure. I mean he knew for sure he didn't do it, how could he, why would he? Memory isn't our only judge of our actions, we know ourselves, and Reid knew himself well enough to know he was not a killer. But now, as his actions cause the potential death of a dozen inmates, is he not a killer?
He rocked himself slowly as he sat on the edge of his bed, his hands running through his hair, the drugs in his system telling him to do the exact opposite of what he knew he must do; stay calm, wait it out. If the guards knew he was high that could get him in trouble, send him to solitary, he would lose any freedoms he has right now. If the guards found out then it could get back to the prosecution, that wouldn't look good, no one could be blamed for drugging him and setting him up in a prison cell. Then he would seem like a junkie and no one trusts a junkie, especially a jury when a murder is involved. For some reason, even though drug addicts tend to be the most vulnerable, helpless and sad people on this earth, it is generally assumed they are dangerous and to be looked down on. Of course, there are cases where drug addicts will become violent to get their fix but it is unfair to generalise, especially when it is more common for a drug addict to be murdered than to be the murderer.
Now he felt more helpless than ever. He did not know that was possible. The day he was arrested he felt helpless, when he found out his prints were on the knife he felt worse, when he was declined bail he thought it was the most helpless he could ever feel. Then he wasn't put into protective custody, then he was beaten up, then his friend was killed. Now, regardless of everything, he cannot figure out a single outcome, let alone every possible outcome. All he can do is sit, and wait, and hope. Hope that Emily and the team can somehow figure out who did it, that if it was Scratch, they can find the evidence to put him away. But, at the moment, the only possible outcome he could imagine would get him out of this place, would be if Scratch handed himself in, and admitted to it all, and somehow, that just didn't seem like a possibility.