Blind trusts, inside information and the ‘mosaic theory’: Why charging members of Congress with insider trading is so fraught

Robert Kelner spoke with Fortune about the recent allegations of politicians committing insider trading and the implications under the STOCK Act. Mr. Kelner says, “Prior to the STOCK Act, it was a source of controversy whether the existing securities laws applied to members of Congress.”

He points to “carve-outs” in Section 10 of the STOCK Act that, while not very clear, are “intended to protect members of Congress in engaging in their constitutional duties.” While no legislators have yet been indicted under the STOCK Act, he believes that “it’s predictable that they would defend themselves based on those constitutional carve-outs.”

In general, congressional insider cases “are not easy cases to prosecute as a criminal matter,” he adds. “Like anything, it’ll depend on the clarity of the evidence available.”