A year after the Boston Marathon bombings, the lone suspect in the case sits in isolation in a federal prison cell 36 miles northwest of Boston, at a facility designed for male inmates with long-term medical or psychological issues.
Federal prosecutors in Dzhokhar Tsarnaev's capital murder and terrorism case on Friday asked a judge to require his defense team to disclose by May 7 whether they'll present any mental health issues during his scheduled November trial.
As recently as late March, Tsarnaev's attorneys said in court filings that the 20-year-old could have been under the "psychological domination" of his older brother, Tamerlan Tsarnaev, who was killed during the massive police manhunt for the pair last April.
Three people were killed and more than 250 injured in the twin April 15, 2013, blasts. Police say the pair built homemade bombs out of pressure cookers and later shot and killed a Massachusetts Institute of Technology police officer while attempting to steal his gun.
Since the younger Tsarnaev was arrested, his defense team has complained in court filings that he has been held in "total isolation" and that the FBI has monitored jailhouse meetings with their client in which they discussed his defense strategy.
Attorney General Eric Holder requested the restrictions last year, saying Tsarnaev was sworn to violence even after his April 19 arrest. Holder cited an interview after Tsarnaev's capture in which he told investigators that he hoped "his actions would inspire others to engage in violent jihad."
In an Aug. 27, 2013, memo, Holder said Tsarnaev had gained "widespread notoriety" in jail and had gotten nearly 1,000 pieces of unsolicited mail. There was "a substantial risk" that allowing Tsarnaev to communicate with others "could result in death or serious bodily injury" to others, Holder said. He released the memo in October.
In December, after Tsarnaev's defense team complained, federal officials said they would ease the restrictions slightly, allowing his attorneys to discuss the case with third parties and allowing a mental health specialist to meet with Tsarnaev without an attorney present.
The federal public defender's office in Boston, which is representing Tsarnaev, said Monday that it won't comment on the case. But in a March 28 filing, the defense team said prosecutors have evidence that could shed light on whether Tsarnaev's older brother "supplied the motivation, planning and ideology" behind the Boston Marathon attack. They're seeking immigration records of the boys' family members and evidence they say shows Tamerlan Tsarnaev "to have had a substantially longer and deeper engagement than his younger brother with extremist and violent ideology."
Evidence from Tamerlan's file is "highly likely" to provide evidence that he was the instigator and leader of the plot and that his younger brother's role "was commensurately smaller," they wrote. Defense attorneys also said prosecutors may have access to evidence showing that the younger brother helped carry out the attacks under the "domination and control" of his older brother. Dzhokhar Tsarnaev was 19 at the time.
After the bombings, the older Tsarnaev was implicated in a 2011 triple murder in Waltham, Mass., and defense attorneys for Dzhokar said the younger brother's awareness of the crime could have led him to see his older brother "as an all-powerful force who could not be ignored or disobeyed." Five weeks after the bombings, a second suspect in the Waltham murders was shot and killed by FBI agents in Orlando, Fla., as he confessed to the killings and implicated Tamerlan Tsarnaev in the crime.
Of the 30 counts in Tsarnaev's June 27, 2013, federal indictment, 17 carry the death penalty.
Contributing: Associated Press