Did Elena Kagan acquit Donald Trump and Chris Christie?

Donald Trump was impeached for abuse of power.  Chris Christie, the unindicted co-conspirator in the "Bridgegate" scandal, like the named defendants was cleared of any federal offense by a unanimous Supreme Court.  Donald Trump exulted.  But, asks a conservative law prof Josh Blackman, did Elena Kagan's Kelly v.U.S. opinion also clear Trump of any impeachable offense?  His Volokh Conspiracy blogpost is spurred in part by this Trump Tweet.

Congratulations to former Governor of New Jersey, Chris Christie, and all others involved, on a complete and total exoneration (with a 9-0 vote by the U.S. Supreme Court) on the Obama DOJ Scam referred to as “Bridgegate.” The Democrats....

— Donald J. Trump (@realDonaldTrump) May 7, 2020

The House Impeachment Committee report suggested that Trump violated the federal wire fraud act 18 USC 1343 - a measure so broad that Jed Rakoff the prominent U.S. District Judge, reflecting on his years as  a federal prosecutor, famously referred to it as "our Stradivarius".  But Elena Kagan announced that 1343 could not play this tune:

The question presented is whether the defendants committed property fraud. The evidence the jury heard no doubt shows wrongdoing—deception, corruption, abuse of power. But the federal fraud statutes at issue do not criminalize all such conduct. Under settled precedent, the officials could violate those laws only if an object of their dishonesty was to obtain the Port Authority's money or property.

As Blackman observes in his blogpost at the conservative, sometimes contrarian blog Volokh Conspiracy, Justice Kagan, who had been the nation's first female Solicitor General, wrote:

As Kelly's own lawyer acknowledged, this case involves an "abuse of power." Tr. of Oral Arg. 19. For no reason other than political payback, Baroni and Kelly used deception to reduce Fort Lee's access lanes to the George Washington Bridge—and thereby jeopardized the safety of the town's residents.

And what is the remedy for a "abuse of power." Kagan writes:

The upshot is that federal fraud law leaves much public corruption to the States (or their electorates) to rectify.

In other words, let the voters decide, said Blackman.  Just like opponents of impeachment argued?  Not a correct decision in my opinion.  I read the unanimous justices as committing an appalling limitation of federal power, leaving to the states the only remedy for such abuses of authority.  But who in New Jersey would go after the Governor?  Not the County Prosecutors who answer to the unelected Attorney General who serves at the pleasure of the Governor.  To my mind Kelly decision has echoes of the post-Reconstruction 1883 abandonment of federal authority to act against private racial discrimination in the ironically titled Civil Rights Cases.

But has the court acquitted Trump? Blackman does not read the Kelly decision so broadly.  He does understand it as a rejection of the argument that impeachment could be grounded in the Wire Fraud.  But he agrees with the House that impeachment need not be tied to violation of any particular federal criminal law.