But immigration lawyers countered that the federal law makes clear that foreigners convicted of murder, rape and other violent offenses can be deported.

They say the ruling offers important protections to immigrants whom the Department of Homeland Security has portrayed as “aggravated felons” based on a broad and vaguely defined category called “crimes of violence,” which may not have resulted in physical harm.

Boston lawyer Matt Cameron said he is aware of “dozens” of immigrants who might be spared from deportation or be allowed to apply for U.S. citizenship because of the ruling.

Among them is a Salvadoran man who grabbed a baseball bat to defend himself after he was followed home by a gang of white men hurling racial slurs at him and then was convicted of a crime. Another, he said, is a man from Cambodia who pleaded guilty to participating in a bar fight, even though he hid in the bathroom.