Amazing how the prospect of having a lethal dose of drugs injected into the bloodstream can change a person’s attitude.

Too bad this epiphany for Joel Courtney happened five years after he murdered Brooke Wilberger.

Courtney admitted this week that in May 2004 he abducted, raped and killed Wilberger, a 19-year-old Brigham Young University student who was working at an apartment complex in Corvallis.

By pleading guilty to aggravated murder, Courtney avoided a possible death sentence. He will be sentenced to life in prison without the chance for parole. That’s good.

But the ugly truth is that Courtney had proved his propensity for sexual violence yet was free to prowl for more victims.

He was convicted of sex abuse in Washington County in 1991. Courtney’s sister told police that he tried to rape her when he was a teenager.

We understand that identifying budding killers like Courtney is a difficult task. And sentencing guidelines make it hard, and in some cases impossible, to permanently imprison people who commit crimes less serious than murder.

But Joel Courtney reminds us that we must be ever vigilant as we try to protect society from its most dangerous predators.