The lawyers said in a court filing yesterday that the FBI has been monitoring the case and that the Bureau of Prisons has tried to screen digital documents they have tried to view with Tsarnaev, in violation of his constitutional rights to prepare his case without government interference.
"These obstacles thwart preparation of important parts of the defense case .... And also threaten the integrity of attorney work product," the lawyers said.
The measures limit Tsarnaev's interaction with people who are helping the defense and restrict the communications and other activities of the defense team, the lawyers said.
They previously asked US District Court Judge George O'Toole Jr. To ease the restrictions. Prosecutors lifted some. The restrictions, known as special administrative measures, are necessary because of the suspect's "commitment to jihad" and "widespread notoriety," prosecutors have said.
Tsarnaev, 20, is accused of building and planting bombs near the finish line of the April 15 marathon, killing three people and injuring more than 260.