For anyone studying the bubbling issue of prosecutor misconduct, the LAT states—Louisiana, Arkansas, and Texas—form a good lab. March alone brewed up:

—belated charges against a prosecutor in Texas, where the defendant was executed a decade ago;

—soul-searching in Louisiana, where a prosecutor bemoaned his win that sent an innocent man to prison;

—and absolution in Arkansas, where the state’s Supreme Court informed me that a prosecutor who withheld critical evidence from a man on trial for his life did not violate any rules of professional conduct.

The Texas case centered on Cameron Todd Willingham, who was executed in 2004 for the arson murder of his three young daughters. Now the State Bar of Texas has filed a formal petition accusing the prosecutor of obstructing justice by making false statements and concealing evidence favorable to Willingham’s defense.

“Before, during and after the 1992 trial, [Jackson] knew of the existence of evidence that tended to negate the guilt of Willingham and failed to disclose that evidence to defense counsel,” the bar said.

It won’t help Willingham, who protested his innocence to the end. But the move suggests that at least some Texans are paying attention.

Next door in Louisiana, a former prosecuting attorney reflected on a conviction he’d won that kept a man on death row for 30 years—and held himself accountable.

“As a prosecutor and officer of the court, I had the duty to prosecute fairly,” attorney A.M. “Marty” Stroud III wrote to a Shreveport newspaper. “Part of my duty was to disclose promptly any exculpatory evidence relating to trial and penalty issues of which I was made aware. My fault was that I was too passive. I did not consider the rumors about the involvement of other parties…”

Stroud agreed that Louisiana owed significant monetary compensation to the man whom he’d helped convict. Yet, he wrote, “The state does not accept any responsibility for the damage suffered by one of its citizens. The bureaucratic response appears to be that nobody did anything intentionally wrong, thus the state has no responsibility. This is nonsensical.”

Noting that evidence that would have cleared the defendant was available at the time of the trial, Stroud wrote: “The easy and convenient argument is that the prosecutors did not know of such evidence, thus they were absolved of any responsibility for the wrongful conviction.”

Stroud dismissed that argument. And he refused to absolve himself.

Last year, 125 men and women were released from prison because they were wrongfully convicted, according to a report by the National Registry of Exonerations. Two-thirds of those cases were overturned because prosecutors either reopened investigations themselves or cooperated with other investigators to ensure that justice was done.

But supreme courts, who bear the ultimate responsibility for the conduct they will accept from attorneys, have stood by like indulgent parents, tolerating outrageous behavior and even ruling that others must too.

(In the infamous Louisiana case of Connick v. Thompson, the U.S. Supreme Court decided in 2011 that a prosecutor could not be held liable for withholding evidence in a murder case because the defendant, who was a month from execution before the withheld evidence was discovered, had not shown that the prosecutor’s office displayed “deliberate indifference” to its duties.)

Echoes of that protectionism can be heard in the Arkansas case of Tim Howard, who will be retried later this month for a double murder that occurred 18 years ago near where these three states join. As I wrote here before, Howard is being retried because after he was sentenced to death, investigations turned up potentially exculpatory evidence that had been withheld from his attorneys.

I know firsthand how loath state officials have been to hold his prosecutor accountable. Four years ago, when I learned of the withheld evidence, I wrote an article for my newspaper first. Then, as a citizen, I wrote a letter to the state supreme court’s Committee on Professional Conduct, complaining about what the prosecutor, Tom Cooper, had done.

Supreme courts routinely sanction lawyers for offenses as minor as misspelled words in briefs or as serious as defrauding clients or showing up drunk in court. I thought that withholding evidence in a death case constituted a gross violation of the court’s Rules of Professional Conduct.

While I didn’t say as much in my letter, I viewed Cooper’s failure to turn over key evidence as horrific neglect, at best. To my mind, it rose to the same level as that of a surgeon who killed by failing to sterilize an instrument, or a driver who ran over a kid while texting. Given the high stakes of a capital trial, there seemed no kinder way to spin it.

The director of the court’s Office of Professional Conduct promptly notified me that he would wait for a court to rule on whether the misconduct I alleged—and which the state’s attorney general by then had tacitly acknowledged—had actually occurred.

The letter also informed me, in all caps and bold type, that I must not disclose the nature of my complaint to anyone, including, ironically, members of the news media. If I did, the letter warned, I could be held in contempt of court and “punished by fine or jail.”

While Howard’s case wound its way back to court for a ruling, I reflected on the Arkansas Supreme Court’s threat. I concluded that it was unlawful, a violation of First Amendment.

I wrote to the committee explaining my concern, but after receiving no response I filed a federal civil rights lawsuit against the state Supreme Court’s Committee on Professional Conduct. That was in 2011.

Arkansas’s attorney general represented the committee. My attorney, Jeff Rosenzweig, argued that the boiler-plate letter I’d received, which went to all persons filing complaints about attorneys, constituted prior restraint and struck at the heart of free-speech protections—protections that were voted into the Bill of Rights particularly so that citizens could discuss their elected officials.

The state never did admit error. But in January 2013, we settled. I withdrew my lawsuit and the court ordered that henceforth the content of complaints could be discussed.

The following November, the judge hearing Howard’s claim about the withheld evidence concluded that misconduct had indeed occurred, though he softened his ruling by opining that the misconduct had been “inadvertent.” Nevertheless, he vacated Howard’s conviction, opening the way for the new trial that will take place this month.

As soon as the judge announced his finding of misconduct, I wrote again to the Office of Professional Conduct. Pointing out that a court had now made a finding of misconduct, I would renew my complaint against Cooper.

Sixteen months passed without a response. During that time I learned that, of the hundreds of attorneys the committee has sanctioned during the past 25 years, not one has been a prosecutor.

I began to think that my letter about Cooper, like my earlier ones about the First Amendment, would be totally ignored. But in the middle of March, just three days after my article about Howard’s upcoming trial appeared here, a letter from the director of the Office of Professional Conduct arrived at my office.

Could it be? A judge had found misconduct serious enough to warrant a new trial for a man who’d spent 16 years on death row, and would the state Supreme Court’s Committee on Professional Conduct finally break with its long tradition and actually punish a prosecutor instead of threatening those who dared to complain about one?

Nope.

This latest letter advised me that, though my complaint against Cooper was “carefully reviewed,” “sufficient evidence” had not been found that Cooper—the former prosecutor who is now a judge—had violated even one tiny rule of professional conduct.

No doubt most defendants facing a judge would love to murmur the word “inadvertent” and be graciously forgiven. But that doesn’t work in America’s courts—unless you’re a prosecuting attorney.