Lawyers say Boston Marathon bomb suspect unfairly restricted

BOSTON - Lawyers for Boston Marathon bombing suspect Dzhokhar Tsarnaev are again asking a federal judge to lift special restrictions that have been placed on their client in prison, saying they are impeding their defense.

The lawyers said in a court filing Thursday 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 U.S. Supreme Court has agreed that a defendant's rights to a lawyer "grants attorneys a zone of privacy within which to prepare the client's case and plan strategy, without undue interference," the lawyers wrote in the filing.

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 U.S. 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.

Also Thursday, O'Toole allowed the appointment of a second attorney with expertise in defending clients facing the death penalty. David Bruck joins death penalty expert Judy Clarke on Tsarnaev's defense team.

Deadly explosions at Boston Marathon 40 photos

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. Authorities say he and his older brother, Tamerlan Tsarnaev, 26, ethnic Chechens from Russia who emigrated to the United States as children, planned and carried out the attack to retaliate against the U.S. for its involvement in Muslim countries.

The younger brother is being held after pleading not guilty to multiple charges. He faces the death penalty if convicted.

Tamerlan Tsarnaev was killed four days after the marathon following a gun battle with police.

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