LAMAR JOHNSON has been imprisoned for nearly 26 years for a murder in Missouri he did not commit. The office that prosecuted him reinvestigated the case two years ago, and concluded that he indeed was wrongly convicted — the result of prosecutorial misconduct and police fabrications. It moved to get him a new trial. But Mr. Johnson, now 47, remains behind bars, and may remain there for years.

The story of Kevin Strickland, 62, is tragically similar. He has been in prison in Missouri for 43 years for a triple murder that prosecutors now say he didn’t commit, and for which they think he should be exonerated. A key witness recanted her testimony against Mr. Strickland, who was then 18, and two men who pleaded guilty in the murders named someone else as their accomplice.

Missouri law inhibits the ability of local prosecutors to correct wrongful convictions, while giving an outsize role to the state’s attorney general’s office — and that office for decades has fought nearly every wrongful conviction case, no matter how compelling the evidence. Injustice Watch, a news nonprofit, has detailed the longtime pattern of both Democratic and Republican attorneys general of stymieing exonerations. The office operates as though its job is to keep convictions intact, “even if you might have convicted an innocent person,” former Missouri Supreme Court chief justice Michael Wolff told the group.

That is the case with Mr. Johnson and Mr. Strickland. For years both men professed their innocence, but only after the Midwest Innocence Project took up their causes were they able to get any kind of traction with prosecutors. Newly established Conviction Integrity Units in the two jurisdictions, St. Louis and Jackson County, launched their own investigations. In Mr. Johnson’s case, investigators found a wealth of evidence that cast serious doubt on his guilt: undisclosed payments to a key eyewitness who has since recanted his identification of Mr. Johnson; credible confessions from two other men who said they committed the murder; and undisclosed information about the criminal history of a jailhouse informant. The findings of the Jackson County prosecutor, submitted for independent review to federal prosecutors, concluded that “Reliable, corroborated evidence now proves that Mr. Strickland is factually innocent of the charges for which he was convicted in 1979. In the interests of justice, Mr. Strickland’s conviction should be set aside, he should be promptly released, and he deserves public exoneration.”

Yet the Missouri Supreme Court ruled against a motion by St. Louis prosecutors — opposed by the state’s attorney general as part of its apparent blanket policy to deny relief — to grant a new trial to Mr. Johnson, and it declined to hear an appeal to release Mr. Strickland. The decisions turned on technical issues and not the innocence or guilt of these men. New habeas petitions have been filed, and legislation that aims to give local prosecutors the means to correct wrongful convictions was passed by the state legislature and, if signed into law, would go into effect on Aug. 28.

Mr. Johnson and Mr. Strickland should not have to wait one more day for their freedom. “If truth matters, if justice is what really is important, why can’t we just get to that?” Mr. Johnson asked in a recent “PBS NewsHour” report that spotlighted his case. Gov. Mike Parson (R) should end the injustice and pardon these two innocent men.

An earlier version of this editorial misspelled the name of Gov. Mike Parson. The error has been corrected.

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