JACKSON, Miss. — Civil rights attorney Benjamin Crump said Monday that he is asking the U.S. Justice Department to investigate why local authorities waited several months to tell a Mississippi mother that her son died after being run over by an off-duty officer.

Dexter Wade, 37, was struck and killed by an off-duty Jackson police officer on March 5 while he was crossing the highway. Wade's mother, Bettersten Wade, filed a missing person's report with the Jackson Police Department days later but never heard back, according to a report by NBC News that made national headlines.

She finally learned her son had been hit by a Jackson Police Department vehicle in late August but wasn't able to retrieve his body until early October — 172 days after she reported him missing. Dexter Wade had been buried in an unmarked grave at a pauper’s cemetery near the Hinds County Penal Farm after his body went unclaimed.

Crump, who took on cases regarding the deaths of Trayvon Martin, Breonna Taylor, and George Floyd, is now calling for justice for the family of Dexter Wade. During a news conference Monday, Crump said Bettersten Wade had no record of Jackson police ever calling her.

"It is certainly suspicious... that they (Jackson police) did not contact her. We don't know what happened in the accident but it would have been better to know on March 5," Crump said during the news conference in Jackson.

Crump added that he is asking the Justice Department to investigate the death because the family "does not have trust in the Mississippi officials."

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What happened to Dexter Wade?

Bettersten Wade last saw her son when he left home on March 5, Crump said. Months later, she learned that her son was crossing Interstate 55 when he was hit by a Jackson Police Department SUV driven by an off-duty officer

During his State of the City speech last week, Jackson Mayor Chokwe Antar Lumumba said Dexter Wade did not have his identification card on him when he was struck and the Jackson Police Department was unable to identify him.

"The accident was investigated, and it was determined that it was, in fact, an accident and that there was no malicious intent," Lumumba said.

According to Lumumba, a coroner identified Dexter Wade through fingerprints and from a bottle of prescription medication he had on him. Crump said the coroner contacted a medical clinic to get information about Dexter Wade’s next of kin but was unable to get in touch with Bettersten Wade.

During the news conference Monday, Crump showed a report that said between March and July the coroner's office called Jackson police seven times to see if they made contact with the next of kin, to which the police department responded no.

Lumumba added that Bettersten was not contacted because "there was a lack of communication with the missing person's division, the coroner's office, and accident investigation," and called it "an unfortunate and tragic incident."

Crump said that he and other attorneys will petition a court to have Dexter Wade's body exhumed and an autopsy performed. He also said Dexter Wade would be given a proper funeral.

In a statement released last week, Hinds County District Attorney Jody Owens said his office is working with Jackson police, the Hinds County Coroner’s Office and other agencies to conduct a review.

Bettersten Wade had previously filed lawsuits against Jackson police

Crump said the Jackson Police Department should have had Bettersten Wade's contact information because she had filed lawsuits against the department after her brother died following a police encounter in January 2019.

Three Jackson police officers were accused of beating 62-year-old George Robinson. Robinson was removed from his vehicle, thrown head-first onto the pavement, and was struck and kicked multiple times in the head and chest.

Robinson had been hospitalized for a stroke days before the police encounter and was on medication. He had a seizure hours after he was beaten, and he died two days later.

Police said they were searching for a murder suspect at the time of the incident.

The death was ruled a homicide. The state medical examiner found that Robinson died of a subdural hemorrhage caused by blunt force trauma to the head, according to Hinds County Coroner Sharon Grisham-Stewart.

Three officers were charged with the killing: Lincoln Lampley, Desmond Barney, and Anthony Fox. Lampley and Barney had second-degree murder charges dismissed in 2022. Fox was convicted of culpable negligence manslaughter and sentenced to five years in prison.

Earlier this year, Mississippi’s Attorney General Lynn Fitch asked the state Court of Appeals to overturn Fox's conviction, citing some medical experts' stance that "it does not require great force to cause a subdural hematoma."

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Bettersten Wade says Jackson Police has 'vendetta' against her family

Bettersten Wade told reporters on Monday that it looks like the Jackson Police Department has a "vendetta" against her family. She believes police were hesitant to tell her what happened to her son because of her brother's death.

"What other reason would you think? Because we went through six months and they don't tell me who my son is. Is it hard for them to connect the dots when you got hospital, coroner and missing person reports," Bettersten Wade said. "That's three reports with my name, my number, so what would you say? When you look at all that evidence, what would you say?"

Crump reiterated her stance during the press conference, saying "all they had to do was knock on her door."

Contributing: The Associated Press