And it must be punished. There are few examples in American crime cases that illuminate the depravity of the criminal mind more clearly than William’s 19 hour rape and torture session that ended with him tying the victim, whom he spent hours trying to blind by pouring bleach in her face, to the bed he tortured her on and setting it on fire.

Miraculously, she survived her ordeal and was able to confront her attacker in court:

A female college graduate student who endured a 19-hour ordeal of rape and torture from a former convict in her flat has faced her attacker in court.

The woman, a 24-year-old student at Columbia University in New York, held her gaze steady as she pointed to 31-year old Robert Williams when asked to identify her assailant.

The witness described at least seven instances of rape, sodomy and forced oral sex over the 19 hours her assailant was in her flat in Manhattan.

Mr Williams tried to force her to blind herself with a butcher’s knife and, when she would not, repeatedly threw bleach in her face, the witness said. He also forced her to ingest massive doses of painkillers, causing her liver failure.

“I was burning all over,” said the woman. “He threw the rest of the bleach into my face, but I was able to close my eyes in time. I was breathing it in. My lungs were burning.”

“I was trying to pretend that I couldn’t see so he wouldn’t pour more bleach in my face. I was nearly hysterical. I was shaking and crying,” said the witness.

He later poured boiling water over her twice and sliced her eyelids, she said. It was after the second scalding, she said, that she asked her attacker to kill her, but he refused.

“No, you’re not good enough for that,” he reportedly said.

He ordered her to stab out her eyes and she nodded.

“I was in so much pain I decided to aim for my neck, and if I died it would be so much quicker than how he was going to do it,” the woman testified. She said she fell toward the knife he had propped up in a pile of clothes, but she missed.

This enraged her attacker, she said, who began to hit her with a heavy object. He then repeatedly beat “my face, my eye sockets, with the blunt end of the knife,” she said. She started screaming but then blacked out

When she came to, she found herself tied to the futon bed of her fifth-floor flat but her assailant had left. Then she smelt smoke and tried to use the fire he had apparently started to burn off her bonds.

In the end she loosed herself from the futon and ran out of the flat, finding a middle-aged couple in the reception who took her to the building superintendent.

Robert Williams deserves to die, but instead faces only life in prison, where he’ll no doubt torture his fellow prisoners the same way. His brave victim spent weeks in three different hospitals, including burn units.

Williams himself is a long time violent felon, whose first murder was a juvenile. He did eight years in the 90s for attempted murder. He was picked up on burglary charges a week later and cops recognized him.

How could a person do such a thing? It’s easy to blame mental illness but the fact is he took pains to hide his crime; he wasn’t out of control. Williams is evil. He liked what he did, he probably did it before and if given the chance he’d do it again. The only way we can ensure that this sub-human doesn’t victimize another person is to end his life.