Two Houston police officers testified Wednesday before a federal grand jury regarding the botched drug raid that left two homeowners dead — the first sign that federal prosecutors are pursuing criminal charges in the controversial case.

Houston Police Officers’ Union Vice President Doug Griffith confirmed that the two officers appeared before the grand jury, though their testimony is secret by law. Grand jury investigations can last weeks or months.

Houston Police Chief Art Acevedo said he was unaware of officers being called by federal authorities to appear before a grand jury.

“We have completed our criminal investigation and are fully cooperating and working collaboratively with the FBI and the Harris County District Attorney’s Office as they conduct separate independent investigations,” he said. “The matter is now in the hands of the District Attorney, the FBI and the United States Attorney’s Office, and further comment would be inappropriate at this time.”

Federal officials would not discuss the case, but Ken Magidson, former U.S. Attorney for the Southern District of Texas, said the grand jury proceedings indicate the gravity of the case.

“It’s a serious matter, because it wouldn’t be brought before a grand jury unless people felt there was sufficient information to believe an indictment is a possibility,” Magidson said.

The two officers called before the grand jury had responded to a call about the house weeks prior to the raid, Griffith said. The now-retired narcotics officers linked most closely to the operation — former case agent Gerald Goines and his partner, Steven Bryant — did not appear before the grand jury Wednesday, he said.

Goines’s attorney, Nicole DeBorde, said she welcomes the federal investigation.

“I anticipate they would do a thorough investigation,” she said. “I have confidence and hope that’s what they’re doing.”

On HoustonChronicle.com: DA threatens to subpoena police for names of informants behind deadly Harding Street drug raid

The Jan. 28 raid on Harding Street in southeast Houston devolved into a firefight as soon as officers broke down the door into the Pecan Park home. Homeowners Dennis Tuttle and his wife, Rhogena Nicholas, were killed in the shoot-out and five officers were injured, including Goines, who was shot in the neck.

Investigators said they raided the Pecan Park home in search of heroin dealers, but the bust only turned up a small amount of cocaine and marijuana — and none of the heroin police expected to find. Investigators have since raised questions about whether Goines lied about the confidential drug buy that he used to justify the raid in seeking a search warrant.

Family members of Tuttle and Nicholas say the two were not drug dealers, and they have hired their own investigators to review the case. They are expected to release the findings of their investigation to the media Thursday.

On HoustonChronicle.com: Harris County DA seeks dismissal of narcotics officer Gerald Goines’ active cases after botched Pecan Park drug raid

Nearly six months later, the ramifications of the raid continue to unfurl. Goines has since retired under investigation, as has his partner, Steven Bryant. The FBI launched a civil rights investigation into the incident and District Attorney Kim Ogg announced prosecutors were reviewing more than 2,000 cases previously handled by Goines and Bryant.

Acevedo dramatically curtailed the use of no-knock raids, and promised to equip raid teams with body cameras.

The news comes the same day investigators from the DA’s Office and the Texas Rangers returned to the Harding Street residence to gather more evidence six months after the shooting.

“Harris County District Attorney’s Office investigators and Texas Rangers were at the Harding Street residence today as part of an ongoing effort to learn all we can about every aspect of the incident that unfolded there,” spokesman Dane Schiller said, in an emailed statement. “We continue our work and have no further comment at this time.”

Griffith said another officer, who is currently assigned to narcotics, has also been subpoenaed to appear.

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