As the federal public defender office in Boston prepares to defend Dzhokhar Tsarnaev, the 19-year-old charged in the Boston Marathon bombings, the lawyers involved face an added challenge: managing the case in the midst of furloughs.

Federally mandated budget cuts known as sequestration could force Tsarnaev’s lawyers to take up to 15 days of unpaid leave before the end of the fiscal year on Sept. 30. Lawyers familiar with the office said it is feeling the pinch in other ways, including leaving vacant positions unfilled.