Updated

Another wrongful death lawsuit has been filed against the federal government in the South Carolina church shootings that claimed the lives of nine black parishioners during a Bible study last year.

Court documents show that Bethane Middleton-Brown filed the suit in federal court last week. She's the sister of the Rev. DePayne Middleton Doctor, one of those killed June 17, 2015, at Emanuel AME Church in Charleston.

The lawsuits claim the FBI negligently failed to check the background of 22-year-old Dylann Roof before he was sold the gun used in the shootings. Roof faces the death penalty in both state and federal courts in upcoming trials.

Court records show the Middleton-Brown suit is the 15th suit filed by both survivors and the families and estates of those killed.