A Texas appeals court Thursday rejected an effort by city attorneys to block lawyers for relatives of two people killed in a deadly Houston police drug raid last year from deposing police supervisors and seeking documents to shed light on the incident.

“This is the key we’re hoping will unlock what happened and who was involved,” said Mike Doyle, an attorney representing the family of Rhogena Nicholas, one of two people killed in the botched raid on Jan. 28, 2019.

Doyle filed a legal petition last summer asking for permission to question police officials under oath about the raid and about alleged “abuses” throughout the narcotics division.

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During the incident, undercover narcotics officers burst into a small home in Pecan Park looking for heroin. A gunfight erupted, resulting in the deaths of Nicholas and her husband, Dennis Tuttle, and injuries to five officers.

The Harris County District Attorney’s Office, the Houston Police Department and the FBI all launched investigations into the incident. In the weeks afterward, authorities said the officer at the center of the incident had lied repeatedly, including about the drug buy he used as the basis for the raid. That officer, Gerald Goines, who retired amid the investigations, is charged with murder and violating the couple’s civil rights.

The Goines case has led to the dismissal of dozens of active cases, and prosecutors now say they believe at least 69 people may have been convicted on false evidence from the former officer. Two men who were convicted and did time because of Goines’ testimony and casework have already seen their cases overturned.

The Houston Chronicle has detailed supervision failures in Goines’ cases, errant raids by narcotics officers, and problems in oversight of confidential-informant funds in undercover units.

After Doyle filed his petition seeking permission to depose some narcotics division supervisors — including Lt. Marsha Todd and Commander Paul Follis, who has since been transferred — the city appealed that request to Texas’ 14th Court of Appeals, arguing that the probate court did not have jurisdiction and other claims.

Doyle filed the petition in probate court because it was already handling legal matters related to Nicholas’ estate, the attorney said.

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In a 13-page ruling dated March 26, three justices from the 14th Court of Appeals picked apart the city’s argument, concluding the probate court where Doyle first filed the legal petition did in fact have jurisdiction over the case, and the claims arising from it.

City officials said they were evaluating their options.

“Today the Fourteenth Court of Appeals affirmed a probate court ruling that it has subject matter jurisdiction over an application for pre-suit depositions,” city spokeswoman Mary Benton said in a written statement. “The ruling addressed only the jurisdictional issue, and not the merits of the motion. The City disagrees with the decision and is evaluating its options for seeking further review.”

The appellate filing comes as federal and state prosecutors continue to pursue cases against Goines and his former partner, Steven Bryant, who also retired under investigation.

A Harris County grand jury indicted Goines on charges of felony murder because the deaths occurred in the course of another alleged felony, tampering with a government record.

In federal court, he is charged with violating the slain couple’s civil rights and multiple instances of tampering. His former partner is charged — in both state and federal court — with tampering with government records. County prosecutors allege Bryant lied in an offense report.

The defense attorney representing Goines said she was continuing to review discovery documents.

“We’re eager to see the details of their investigations,” Nicole DeBorde said.

DeBorde said she wasn’t surprised Doyle was pursuing a possible lawsuit against the city.

“I think that’s what this has always been about for them,” she said.

st.john.smith@chron.com