Laurence Tribe, the Constitutional law prof at Harvard, has concerns about Bernie.

[The Velveteen Ocelot]

95. Actually he's been a strong opponent of the Citizens United case.

He's drafted a proposed constitutional amendment that would effectively overturn Citizens United. https://www.theatlantic.com/politics/archive/2012/07/the-supreme-court-still-thinks-corporations-are-people/259995/ His work for corporations hasn't been to further the simple-minded notion that corporations are people (everyone knows they aren't), but that they have certain constitutional protections. In the Peabody case he argued that the EPA rule in question violates the Fifth Amendment because it constitutes a regulatory "taking" by the federal government in the sense that it limits the corporation's use of its properties without due compensation, and that it violates the Tenth Amendment by coercing states into creating their own CO2 reduction plans or else risking the federal government imposing its own plan. The argument was nuanced and complex and had much to do with the details of administrative law and procedure. The cases were controversial and there are, indeed, some lawyers who believe Tribe's arguments in these cases were not very good ones (in fact, he lost the GE case).

This, of course, has no bearing on whether he's right or wrong about Bernie.