BOSTON (AP) -- Every time the widow of suspected Boston Marathon bomber Tamerlan Tsarnaev leaves her parents' house, federal agents watching the residence follow her in unmarked vehicles.
Federal authorities are placing intense pressure on what they know to be the inner circle of the two bombing suspects, arresting three college buddies of surviving brother Dzhokhar Tsarnaev, and keeping Tamerlan's 24-year-old widow, Katherine Russell, in the public eye with their open surveillance and leaks to media about investigators' focus on her.
Legal experts say it's part of their quest not just to determine whether Russell and the friends are culpable but also to push for as much information as possible regarding whether the bombing suspects had ties to a terrorism network or accomplices working domestically or abroad. A primary goal is to push the widow and friends to give their full cooperation, according to the experts.
David Zlotnick, a professor of law at Roger Williams University and former federal prosecutor in the District of Columbia, said authorities may be tracking Russell closely because they feel she's not being completely honest about all she knows.
Tamerlan's widow has been ensconced at her parents' North Kingstown home since then. Much about her remains a mystery, including what she knew or witnessed in the weeks, months and years before the bombings, and what she saw and did in the days after.
It's unclear when Russell last communicated with her husband, but her lawyer, Amato DeLuca, told The Associated Press in an interview last month that the last time she saw him was before she went to work April 18. DeLuca said Tuesday that Russell had met with law enforcement "for many hours over the past week," and would continue to do so in the coming days. He previously told the AP that Russell didn't suspect her husband of anything before the bombings, and nothing seemed amiss in the days after.
Zlotnick said the fact that charges have been brought against the younger brother's three friends from the University of Massachusetts Dartmouth over allegations they covered up for Dzhokhar indicates authorities are willing to go after the widow for similar actions. That puts pressure on Russell to cooperate.