NEW YORK — Boston Marathon bombing defendant Dzhokhar Tsarnaev says U.S. prosecutors are wrongfully barring him from talking privately with his two sisters by suggesting the women may engage in “terrorist tradecraft.”

The U.S. is exaggerating the risk of such meetings and shouldn’t be present when Tsarnaev, 20, meets with his siblings and defense-team investigators in prison, one of his lawyers, David Bruck, said Monday in a filing in Boston federal court.

Terrorists who are inspired by the April 2013 double bombing at the landmark marathon’s finish line may attempt to communicate with Tsarnaev through his sisters, prosecutors argued at an April 16 hearing and in court filings. The sisters may act as intermediaries even if they aren’t aware of it, the U.S. government said.

“Raising such paper-thin concerns about security is a no-lose proposition for the government, because even the flimsiest of arguments, once ominously repeated and amplified by the news media, will inevitably tend to inflame the public’s fear of the defendant,” Bruck said in Monday’s filing.

Tsarnaev’s star defense lawyers, who have worked on some of highest profile death-penalty cases in the United States, are grappling with prosecutors over their client’s unmonitored access to his family three weeks after Boston observed the first anniversary of the attack, in which three people were killed and 260 were injured. A trial is scheduled for November.

Tsarnaev’s mother Zubeidat Tsarnaeva had referred to the presence of unspecified “friends” of his brother Tamerlan Tsarnaev, the other suspect who was killed in a police shootout after the bombing, during government-monitored and recorded phone calls, the U.S. has argued. Tsarnaeva talked with her son from Makhachkala, the capital of Russia’s Dagestan region that is roiled by an Islamist separatist movement.

Bruck earlier this month said in court filings that Dzhokhar Tsarnaev’s foreign birth and immigration history are being misused by prosecutors who accused him of betraying the United States in their formal justification for seeking the death penalty.

Dzhokhar Tsarnaev received asylum in the U.S. when he was 8 years old and took the oath of citizenship seven months before the attack.

Bruck is seeking a court order barring the government from using Dzhokhar Tsarnaev’s path to U.S. citizenship to convince a jury that he is more deserving of the death penalty, if he’s convicted of the terror attack, Bruck said.

In a separate filing, his lawyers asked that the judge stop the “flow of leaks and inappropriate public comments” by law enforcement involved in the investigation, including on a “60 Minutes” segment last month, which they said may violate Dzhokhar Tsarnaev’s right to a fair trial.

Dzhokhar Tsarnaev was inspired by al-Qaida and motivated by the U.S. military’s killing of Muslim civilians, prosecutors have said. He pleaded not guilty in July to 30 counts, including allegations that he killed a university police officer in the days after the attack.

Last month, his defense team lost a bid to force the U.S. to turn over evidence that may show Dzhokhar Tsarnaev’s older brother radicalized him and led the attack – evidence they said may persuade a jury to spare his life if he’s convicted.

The request for material about Tamerlan Tsarnaev was denied by U.S. District Judge George A. O’Toole Jr., who didn’t elaborate on the decision.

The Tsarnaevs, immigrants of Chechen descent, had lived in the U.S. for more than a decade.