In court and at the negotiation table, U.S. Justice Department prosecutors and defense lawyers from big firms often take differing views of the law. Less common is the case in which a different view of the law makes the firm, and not the client, the focus of a government investigation.

Clifford Chance found itself in that position over its apparent misunderstanding of data-access regulations concerning the export of defense and military equipment. On Wednesday, the firm agreed to pay a $132,000 civil penalty, along with lost wages to three unidentified individuals, to resolve a Justice Department investigation into the firm’s refusal last year to allow dual citizens and non-U.S. citizens to work on a document review project.