From the late 1970s into the mid-1980s, Rosenberg was active in the far-left terrorist[2][3][4] May 19th Communist Organization ("M19CO") which, according to a contemporaneous FBI report, "openly advocate[d] the overthrow of the U.S. Government through armed struggle and the use of violence".
She had also been sought as an accomplice in the 1979 prison escape of Assata Shakur and in the 1981 Brink's robbery that resulted in the deaths of two police officers and a guard,[7] although she was never charged in either case.
[15][10][16] Arrested in November 1984 for possession of over 750 lbs of explosives, after three years underground following the Brink's robbery, Rosenberg was convicted in March 1985 by a federal jury in New Jersey and given a 58-year-sentence.
[22] After touring the unit, the American Civil Liberties Union denounced it as a "living tomb", and Amnesty International called it "deliberately and gratuitously oppressive".
[25] After her release, Rosenberg became the communications director for the American Jewish World Service, an international development and human rights organization, based in New York City.
She also continued her work as an anti-prison activist, and taught literature at John Jay College of Criminal Justice, in Midtown Manhattan, New York City.
After teaching for four semesters there as an adjunct instructor, the CUNY administration, responding to political pressure, forced John Jay College to end its association with Rosenberg, and her contract with the school was allowed to expire without her being rehired.
[27] As of 2020, Rosenberg serves as vice chair of the board of directors of Thousand Currents, a non-profit foundation[28] that raises funds and provides institutional support for grassroots groups, particularly in the Global South.