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. 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. 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