Tonight at 10 p.m. local (U.S. Central) time* in Sioux Falls, South Dakota will administer a toxic lethal injection to Eric Robert … with Robert’s complete consent. (Update: Robert has indeed been executed as scheduled.)

Robert will reach the gurney on the greased-lightning legal path, thanks to his own willingness to die.

It’s a mere 18 months since Robert (then serving a prison term for kidnapping) and another convict murdered guard Ronald “RJ” Johnson for his uniform during an unsuccessful escape attempt.

Robert pled guilty, requested the death penalty, and waived his appeals. This phenomenon is surprisingly common; the Death Penalty Information Center’s invaluable executions database classifies over 10% of modern U.S. executions as voluntary. (138 volunteers out of 1,308 total executions as of this writing: Robert will be the 139th and 1,309th)

While many of those abandoned their appeals in despair once they’d been on death row for a while, Robert has shown uncommon clarity of purpose from the very first, and his firm and intelligent resistance to any attempt to intervene against his death sentence has undermined any possible argument that the guy isn’t in his right mind. So far as anyone can tell, he sincerely believes in a retributive criminal justice ethos.

It might help that the man has followed an atypical criminal arc. He has a biology degree and was a law-abiding wastewater treatment supervisor and Little League coach until he weirdly posed as a police officer and kidnapped a teenager in 2005.** (He says he was drunk.)

Robert even complained publicly when South Dakota nixed a spring 2012 execution date to conduct the mandatory appellate review all capital cases receive; he wrote a letter to the Associated Press saying that he would kill again.

“Victims of non-capital offenses receive their justice when the perpetrator is placed in custody,” Robert wrote. “Victims in capital cases receive their justice when the perpetrator is executed.” That might indeed constitute a persuasive reason to execute Eric Robert, though the same logic would just as readily dispute the suitability of the death penalty as public policy. It’s invariably justice delayed, after all.

I am free to admit my guilt, as well as acknowledge and accept society’s punishment just as I am free to proclaim innocence in defiance of a verdict. I believe that the sentence of death is justly deserved in any murder and should be carried out … Give the Ron Johnson family their justice, they have been forced to wait too long. I finish where I started — I deserve to die.

The court soon obliged him. With legal interventions seemingly at an end and no reason to expect a change of heart from Robert (who could stop the proceeding at any time by announcing his intent to file additional appeals) his execution tonight appears to be inevitable.

And if legal maneuvering has been light, South Dakota — whose 2007 execution of Elijah Page, another volunteer, was the first in that state since the Truman administration — has not been spared the lethal injection misadventures that have bedeviled American death chambers the country over.

Sodium thiopental, one of the drugs used in the classic three-drug lethal injection cocktail, has become very hard to come by for executions. In 2011, South Dakota was exposed for having purchased a supply of unlicensed thiopental from the India company Kayem Pharamaceuticals.

That led South Dakota to switch its lethal injection process to instead use pentobarbital, again following a nationwide trend. Pentobarbital executions have been subject to their own legal challenges, and in South Dakota such suits have been pushed by advocates for Donald Moeller.

Moeller is the next man scheduled to die at Sioux Falls; like Robert, he’s a volunteer, and he’s successfully rejected the “assistance” of the pentobarbital appeal. If all goes to plan Moeller will die during the week of Halloween: two executions in three weeks for a state where the death chamber went unused for a lifetime.

* See this handy list of the times of day each U.S. jurisdiction conducts its executions. The time is rather unusual; many states have moved away from the stereotypical “midnight assassination” late-night execution in favor of something more proximate to business hours.

** The available public evidence suggests Robert perhaps (and understandably) loathes incarceration; rather than shibboleths about society’s punishment, Robert fought to reduce his kidnapping sentence to bring a potential parole opportunity within his grasp. The escape attempt and bluster about killing people happened after those kidnapping appeals foundered.

On this day..

• 1948: Arthur Eggers, by Earl Warren
• 1794: Robert Watt, British Conventioner
• 1660: John Carew, regicide
• 1767: Tom, slave of the Baylor family
• 1937: Panfiliya Tanailidi, Azerbaijani actress
• 1651: James Stanley, Earl of Derby
• 1942: Coastwatchers on Tarawa
• 1940: Lluis Companys, Catalan president
• 1964: Nguyen Van Troi, Viet Cong urban guerrilla
• 1942: Three Doolittle raiders
• 1896: Rainandriamampandry and Prince Ratsimamanga
• 1917: Mata Hari, femme fatale
• Themed Set: Belles Epoque