HOUSTON — Prosecutors on Friday said they plan to dismiss 27 pending court cases linked to two former Houston police officers who are being investigated following a deadly drug raid in January.

The Harris County District Attorney’s Office said the cases are being dismissed “due to concerns about the credibility” of former officers Gerald Goines and Steven Bryant.

“Truthfulness is essential in a case that must be proved beyond a reasonable doubt. We can’t vouch for these officers’ credibility,” Harris County District Attorney Kim Ogg said in a statement.

Goines and three other officers were shot in a gunfight that killed 59-year-old Dennis Tuttle and 58-year-old Rhogena Nicholas, who both lived in the home where the raid occurred on Jan. 28. A fifth officer injured his knee during the shooting.

Bryant and Goines were relieved of duty after the deadly raid in a working-class Houston neighborhood.

Authorities allege Goines lied in a search warrant affidavit when he said that a confidential informant had bought heroin at the home. But the informant told investigators no such drug buy ever took place. Goines had indicated in the search warrant that Bryant had identified heroin bought at the home. But Bryant later told investigators he had retrieved heroin from Goines’ police car.

Goines and Bryant later retired.

Family and friends of Tuttle and Nicholas have said the two, who were married for 20 years, were not criminals. They have angrily dismissed the allegations that the couple was selling heroin and had fired on officers while defending an illicit business.

The district attorney’s office said it planned to file the motions to dismiss the cases connected to Goines and Bryant on Friday. The two officers were material witnesses in the cases who could be required to testify, prosecutors said.

The cases involved a total of 25 defendants. All of the cases except one were for possessing or selling drugs. The other case was for possessing a firearm as a felon.

The oldest of these cases dates back to May 2017, while the most recent was from Jan. 28, the same day as the deadly drug raid.

At least four other cases have previously been dismissed, according to the district attorney’s office.

“Police corruption erodes public trust and through methodical, deliberate and independent investigation, we will get to the truth,” Ogg said.

Norm Silverman, an attorney who represents two half brothers whose cases were among the 27 dismissed, said he’s grateful that Ogg’s office “did the right thing.”

He said he hopes the office will continue to review closed cases. He alleges that both of his clients “have been prosecuted in the past based on similar shoddy work by Officer Goines.”

The attorney said he is working to challenge a 2007 conviction of one of his clients, a conviction that was based in part on the work of Goines.

Goines’ attorney, Nicole DeBorde, has previously said her client is innocent of any crime.

Prosecutors had previously announced that they are reviewing more than 2,000 cases linked to Goines and Bryant.

In addition to an internal review by Houston police, the FBI is conducting an investigation to determine whether any civil rights were violated as a result of the raid and shooting.