The antifederalists looked to impeachment as a prime example of everything that was wrong with the Senate. Despite the expectations of the Constitutional Convention, the antifederalists did not think the Senate would ever remove the president, much less any other official it approved of. “Should he, contrary to probability, be impeached, he is afterwards to be tried and adjudged by the Senate, and without the concurrence of two-thirds of the members who shall be present, he cannot be convicted — This Senate being constituted a privy council to the President, it is probable many of its leading and influential members may have advised or concurred in the very measures for which he may be impeached,” Luther Martin, a delegate to the Constitutional Convention, observed in his November 1787 address to the Maryland legislature.

Likewise, the writer known as “Federal Farmer” argued that the high bar to removal and the deep entanglement of the Senate and the executive meant the impeachment power was practically a dead letter. “Under these circumstances the right of impeachment, in the House, can be of but little importance; the House cannot expect often to convict the offender, and, therefore, probably, will but seldom or never exercise the right.” And in an unpublished pamphlet, a young James Monroe levied a similar critique of impeachment. “In the operation of this government,” Monroe wrote, there might be offices “committed against one quarter of the community” that would be “highly beneficial to others.” In such a case, he asked, “could we expect from the representatives of these states a candid or impartial decision against the interests of their constituents?”

If we define the “interests of their constituents” as partisan interests — who wins, who loses — then, to answer Monroe, we cannot actually expect those representatives to make a “candid or impartial decision” against the president when he’s on the same side. It’s what we saw with the Clinton impeachment and it’s what we see now, as Republicans embrace Trump and rally to his defense.

The Senate has not been a cabal in most of the ways antifederalists feared. Senators have not conspired to make themselves a permanent aristocracy or make seditious treaties with foreign powers. But the advent of political parties, the rise of strong partisanship and the growth of hyperpolarization have created something of a “conspiratorial den” among co-partisans in ostensibly rival branches of government. Republican lawmakers have an interest in the political survival of the Republican president, just as Democratic lawmakers have an equivalent interest in the survival of a Democratic president. And for Republicans under Trump specifically, their political survival depends on, in Luther Martin’s words, “the favour of the President.” Just ask Jeff Flake.

The trial against our corrupt chief executive is clearly slanted in his favor. If the antifederalist opponents of the Constitution could see us struggling now, they might just say, “We told you so.”

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