BOSTON (AP) -- A federal judge ruled Wednesday that "betrayal of the United States" should not be a factor in considering whether Boston Marathon bombing suspect Dzhokhar Tsarnaev gets the death penalty if convicted.
U.S. District Court Judge George O'Toole said it was "highly inappropriate" for prosecutors to draw a distinction between a "naturalized" and "natural-born" U.S. citizen.
Federal prosecutors have argued, in part, that Tsarnaev, a 20-year-old Russian-born immigrant, deserves the death penalty because he betrayed his allegiance to the U.S., which gave his family asylum and citizenship more than a decade ago.
Tsarnaev's attorneys have said that argument is unprecedented in death penalty cases.
"(I)n not one of the 492 cases before Mr. Tsarnaev's has the government cited the fact of a defendant's American citizenship, the way he became a citizen, any aspect of his immigration history, or his enjoyment of the freedoms of an American citizen as a reason to sentence him to death," they wrote in a May filing.
O'Toole agreed with defense attorneys who said prosecutors would have many other factors to cite in their bid to seek the death penalty if Tsarnaev is convicted.
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O'Toole also denied a request by Tsarnaev's lawyers to allow them to meet with their client and his sisters in prison without federal agents present. Instead, he accepted a compromise offered by prosecutors: assigning an agent or other federal official not related to the case, strictly for security.
And the judge issued a stern warning to prosecutors about former or current members of its team speaking to the media. The warning comes after the defense objected to what it called leaks from retired FBI agent during interviews they gave around the April anniversary of the bombings.
However, O'Toole declined to impose sanctions on prosecutors if such disclosures happen again, as Tsarnaev's lawyers sought. Prosecutors have said the interviews contained information that was already public.
One key question not addressed at the hearing was the Wednesday deadline for the defense to formally request to move the trial out of Boston.
Tsarnaev's lawyers have stated they will pursue a venue change, citing the intense media coverage of the case.
The defense had wanted until Aug. 3. to craft its legal argument. But O'Toole denied that request last week after already pushing the deadline back once before, from Feb. 28 to June 18.
Prosecutors say Tsarnaev and his brother, Tamerlan, planted two bombs that exploded near the finish line of the 2013 marathon, killing three people and injured about 260 others. Tamerlan died following a shootout with police several days later.
Dzhokhar Tsarnaev has pleaded not guilty to 30 federal charges. His trial is expected to begin in November.