How about some names?
Tribe did not say he was backing Trump. If anything Tribe, who was Ted's professor at Harvard, said Ted was eligible, but the matter was not settled by a court. Which is true.
Who else who is strongly supporting Hillary has backed Trump? After all, the plural sense was used here.
Reading the Tribe article, as it appeared in the Boston Globe, what Tribe actually said that Cruz continually argued with him when Cruz was a student in his Con law class and that Cruz argued from a constitutional originalist position while, he, Tribe, favored the living constitution approach (the position which was advocated by the racist, eugenics believing social Darwinist Woodrow Wilson). Trump goes on in the article to say that under his living, evolving constitutional interpretation approach Cruz would be eligible but not under Cruz’ constitutional originalist viewpoint.