The family of Irvo Otieno -- who died in March while being admitted to a Virginia mental health facility -- is asking the Department of Justice for a federal investigation into his death, their attorneys announced Wednesday.
Seven sheriff's deputies and one hospital worker are facing second-degree murder charges in 28-year-old Otieno's death, which was ruled a homicide by asphyxiation by the Office of the Chief Medical Examiner of Virginia.
The workers "smothered him to death" during the facility's intake process, former Dinwiddie County Commonwealth's Attorney Ann Baskervill has said.
"The resources of the U.S. Department of Justice are necessary to ably and properly prosecute the defendants," Otieno family attorneys Ben Crump and Mark Krudys wrote in a letter to the Department of Justice Civil Rights Division.
The request for a federal criminal investigation comes after Baskervill -- who filed the charges in the case -- resigned her position last week.
One day before her resignation took effect, Baskervill dropped charges against two of the original 10 defendants in the case.
The decision to drop charges against two hospital employees "was heavy but it was not difficult," Baskervill told CNN affiliate WTVR. Her resignation was due to personal health issues and is unrelated to the Otieno case, Baskervill told the station.
The attorneys for Otieno's family told the Justice Department that her replacement, interim Commonwealth's Attorney Jonathan Bourlier, has "no prosecutorial experience and minimal trial experience." CNN reached out to Bourlier Wednesday for comment.
Otieno's family has said he was in the midst of a mental health crisis when he was being processed at the hospital.
Henrico County police officers first encountered Otieno on March 3 after they responded to a possible burglary and placed him under an emergency custody order. Under Virginia law, a person may be placed under an emergency custody order if there are concerns they may harm themselves or others as a result of mental illness.
The officers took Otieno to a hospital where authorities say he became "physically assaultive" towards officers. Police took him to Henrico County Jail and he was booked.
Three days later, Otieno was transferred to the mental health facility in Dinwiddie County where he died during the intake process. State police investigators were later told Otieno became "combative" and was "physically restrained," the attorney's office said in a statement on March 14.
Surveillance video showed Otieno was held on the ground in handcuffs and leg irons for 12 minutes. Additional video showed he had previously been kept in a holding cell at the Henrico County Jail, where he was naked and pepper-sprayed by deputies, according to prosecutors.
"The federal civil rights laws outlawing the application of excessive force by law enforcement officers are the appropriate vehicle to address the eight defendants' conduct," attorneys Crump and Krudys wrote.
The defendants were released on bond, with the next hearings in their cases set for August. The Henrico Fraternal Order of Police Lodge 4 has said it stands behind the deputies charged.
CNN reached out Wednesday to the US Attorney's Office for the Eastern District of Virginia and the Civil Rights Division of the Justice Department for comment.