Someone on YTDAW mentioned that her father was a guard in the same prison that Richard Speck (the real-life sociopath whose crimes this episode was modeled on) was in. She said that her father crossed paths with Speck at one point, and that his eyes were so dead and yet so evil, it scared the s**t out of him. I thought that was an interesting connection.
BTW, anyone who wants to read about Richard Speck can get the details at
Wikipedia, and in far more detail at
Crime Library.
I also just wanted to point out that it's entirely possible that the killer in the episode did not cut his own throat out of remorse. It's entirely possible that, clinically, he knew he felt nothing about killing the victims and just wanted to see if he would feel anything by slitting his own throat. Knowing that he was in a public place and that someone would be likely to find him, he could be reasonably sure that he wouldn't bleed to death before getting to a hospital, especially if he was careful not to slit his throat from end to end. Which, if I remember correctly from his bandages in the hospital, he didn't.
At any rate, if you read the page above you will see that the real Speck
did attempt suicide before he was caught. Maybe he wanted to see if he could feel something, like I said. Maybe he thought his life sucked for other reasons and wanted to end it. Maybe he figured he'd be caught and was calculatingly making a bid for sympathy. But if the real-life guy tried it, then I don't think there's any grounds for saying that TPTB did a poor job because they wrote the killer that way.
It sure does prove, though, that sometimes real life really is stranger than just about anything we can imagine.