Courtesy Robinson Family
Shanquella Robinson
CNN  — 

Federal prosecutors told the family of Shanquella Robinson on Wednesday that the evidence they have isn’t enough for prosecution in Robinson’s death last year in Mexico, the US Attorneys’ Offices for the Middle and Western Districts of North Carolina said.

Robinson, a 25-year-old former student at Winston-Salem State University in North Carolina, died in October while staying in a luxury rental property in the Mexican state of Baja California Sur.

“Based on the results of the autopsy and after a careful deliberation and review of the investigative materials by both U.S. Attorneys’ Offices, federal prosecutors informed Ms. Robinson’s family today that the available evidence does not support a federal prosecution,” the US Attorneys’ Offices said in a release Wednesday.

Family members are “very deeply disappointed” in the decision, but are “not deterred” and plan to continue to seek justice for Robinson, their attorney, Sue-Ann Robinson, said at a news conference.

“Black and brown people always have to carve their own path to justice,” attorney Robinson said. Shanquella Robinson was a Black American from North Carolina.

A copy of Shanquella Robinson’s death certificate, obtained by CNN affiliate WBTV, listed the cause of death as “severe spinal cord injury and atlas luxation,” which is instability or excessive movement in the uppermost neck vertebrae. The document stated she was found unconscious in the living room of the rental residence on October 29.

The death certificate classified Shanquella Robinson’s death as “accidental or violent,” noting that the approximate time between injury and death was 15 minutes.

Video posted online appeared to show a physical altercation inside a room between Shanquella Robinson and another person. It’s not clear when the video was taken or if the video depicted the moment she suffered the fatal injury.

At the time, Bernard Robinson confirmed to CNN it is his daughter seen in the video being thrown to the floor and beaten on the head.

It’s unclear what led to the altercation or how many people were in the room at the time. It’s also unclear if anyone tried to intervene.

The FBI conducted “a detailed and thorough investigation of the evidence” and worked with the Robinson family to conduct an autopsy in the United States by the Medical Examiner’s Office in Mecklenburg County, North Carolina, the release said.

Federal officials met with the Robinson family and representatives on Wednesday “to offer their condolences and present the findings of the federal investigation,” the release said.

According to attorney Robinson, the family was told that the FBI interviewed Shanquella Robinson’s travel mates and “people who were in the house,” but did not specify how many people they interviewed.

The US officials told the family that the autopsy, which was completed after Shanquella Robinson’s body had been embalmed and transported back to the US, revealed no spinal cord injury but did show swelling on her brain, although the cause of death is still said to be undetermined, the attorney said.

The attorney criticized what she considered a delay on the part of US investigating agencies, saying they waited to investigate until after their own autopsy was conducted.

“There was no swift action on this case. There was absolutely no urgency on the part of the US authorities,” Sue-Ann Robinson added.

“If you wait ‘till five months after someone committed a crime… they would have the opportunity and time and space to delete text messages if that’s what they wanted to do, to talk to each other about the case,” the attorney said.

Federal officials said they do not normally issue public statements about the status of an investigation, but in this case, they felt it was necessary because of the public concern surrounding the case.

“It is important to reassure the public that experienced federal agents and seasoned prosecutors extensively reviewed the available evidence and have concluded that federal charges cannot be pursued,” the statement said.

Prosecutors in Mexico said last year they were investigating Robinson’s death as femicide, a crime defined as the “intentional murder of women because they are women.” 

In most countries, including the United States, femicide is not different from homicide in criminal law, but Mexico is among at least 16 countries that have included femicide as a specific crime.

The family plans to hold a march to the State Department headquarters Washington, DC, on May 19, the 200th day since Shanquella Robinson’s passing, according to the family’s attorney.

“The message cannot be that US citizens can go overseas and commit crimes against other US citizens and come back and say that they’re on base, that they’re safe, that they’re not gonna be arrested, that there’s gonna to be such a delay in the investigation that the evidence will have time to dissipate,” she said.

CNN’s Hannah Sarisohn and Jamiel Lynch contributed to this report.