Serving life without parole is not the big easy. Prisoners who are sentenced to live behind bars every day until they die are not spending their hours watching football games in air-conditioned cells.

But imagine if you didn't know that. Imagine that all you ever heard was the false tale, so often depicted in the media, that incarceration until death is like being locked in a country club. If you'd never heard the truth that being sentenced to a small, sometimes crowded and sometimes painfully isolated cement cell means suffering every day, it would be hard to know that life without parole is an extreme and excruciating punishment.

In Mississippi and at least three other states, juries don't get to hear testimony about the true conditions of life behind bars. In a data-driven society where we demand information for the most mundane of choices, this artificial suppression of important facts reminds me of the old Pepsi Challenge, but with a patently unfair twist: this time the taster has to pick between Pepsi and Coca Cola without even tasting the Coke. That's no way to pick a cola, and it's certainly no way to pick who should live and who should die.

In a petition for certiorari we recently filed in the U.S. Supreme Court, we challenge a death sentence the State of Mississippi obtained against our client, Leslie Galloway III, by artificially tilting the scales of justice in the state's favor. The State convinced the jury to have Mr. Galloway executed by forbidding it from hearing anything about the harsh conditions Mr. Galloway would face in a Mississippi prison if the jury chose a sentence of life imprisonment without parole instead of execution.

Mr. Galloway was convicted of capital murder in 2010. Upon convicting him, his jury became responsible for the single most difficult task we ask of juries in this land – to decide if he should live out the rest of his days locked in prison, or if the State should strap him to a gurney and execute him. When the prosecutor stands up and tells the jury that only execution would be just (as the prosecutor claimed in this case), the jury needs an answer to the question: in comparison to what? Juries should get enough information to understand not only the crime and the details of the defendant's life leading up to the crime, but they should also get to know what a life sentence looks like to assess if it is the appropriate punishment – would the prisoner be sitting in an air conditioned cell watching ESPN all day, with privileges and freedoms that would give him opportunities to hurt others, or would he truly suffer in prison and be kept under close guard?

At Mr. Galloway's trial for his life, his defense team was prepared to present the testimony of Donald Cabana, who had long served as superintendent of the Mississippi State Prison at Parchman. If permitted to testify, Cabana would have set the record straight by telling the jury that Galloway "is not going to be in an air conditioned cell, he is not going to [get his own cell,] and he is going to be suffering every day, a horrible existence, and they need to know that." But, on the prosecutor's motion, the Mississippi courts blocked this testimony completely.

Many jurors and a substantial portion of the public believe that life imprisonment without parole can be adequate punishment, even for very heinous crimes. In many states that still have the death penalty on the books, testimony about the prison conditions that life imprisonment entails is an important part of capital trials. By artificially excluding from the jury's consideration the true conditions of imprisonment, Mississippi turned Lady Justice on her head in order to secure a death sentence for Mr. Galloway.

Death sentences based on misinformation are sadly a part of our broken death penalty system, leading to reversal after reversal. This petition gives the Supreme Court an opportunity to fix a death sentence based on a lack of information crucial to the jury's verdict. For the sake of Leslie Galloway, let's hope the Court grants it.

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