Mr. Trentadue spent the past 13 years trying to find out why his brother died in a federal prison in Oklahoma and approached everyone from former federal agents to convicted Oklahoma City bomber conspirator Terry Lynn Nichols.
Mr. White was charged with fatally running over a Prince George's police officer. He was held in a cell separate from other prisoners for his safety. State and federal investigations are pending in his strangling death, and county officials ordered jail guards to cooperate with the probe Wednesday after reports surfaced that some had refused to speak with investigators.
But Mr. Trentadue advised family members waiting for answers to steel themselves.
"It's just a horrible fight, a horrible fight," he said Wednesday.
His younger brother, Kenneth, died in an Oklahoma City federal prison in August 1995 after being arrested on a parole violation. Officials said Mr. Trentadue's brother committed suicide by hanging himself in his prison cell with a braided bed sheet.
But when the Trentadue family asked authorities to release their brother's body to them, they found a corpse marred with bruises and lacerations that a medical examiner later determined were consistent with strangulation.
Mr. Trentadue said he thinks that federal authorities accidentally tagged his brother as "John Doe No. 2" - America's most-wanted criminal at the time of the Oklahoma City bombing.
Since then, the Trentadue family has fought with federal authorities for more information about Kenneth's death, placing an enlarged photo of Kenneth's autopsy on a billboard in Florida and seeking a deposition from Terry Nichols, who is serving a life sentence for helping Timothy McVeigh in the Oklahoma City bombing in 1995.
The NAACP on Wednesday called for the suspension of nine corrections officers who had been charged with watching Mr. White at the Prince George's Corrections Center.
County safety director Vernon Herron told corrections officers that they would have to cooperate with the probe or face disciplinary action after four of the officers reportedly declined to cooperate with state and federal investigators.
Mr. Trentadue, a Salt Lake City trial lawyer, said he has closely followed news of Mr. White's death this week and was struck when he learned that two small bones had been broken in his neck, indicating strangulation.
"That fractured hyoid bone tells all, my brother had all of the classic signs of strangulation," he said.
Mr. Trentadue urged the White family to stay strong.
"It will be a tremendous fight, and it will take a lot of resources not only financially, but physically, mentally and emotionally," he said.