With the alleged Articles of Impeachment now before the Senate, the so-called "obstruction of Congress" charge will doubtlessly be summarily dismissed upon precedence.
"Obstruction of Congress" is the equivalent of "contempt". Cleverly disguised, perhaps, but semantically an equivalent term nevertheless.
However, Congress (specifically the hyper-partisan led House) lacks constitutional authority or even the general power to punish said "obstructive" contempt.
It would not be a surprise if the basis for dismissal of this specific "article" turns out to be the Supreme Court decision Kilbourn v. Thompson, 103 U.S. 168 (1880).
Kilbourn (brough in 1876, decided in 1880) involved Congress' attempts to coerce a witness upon the claim that "this power exists as one necessary to enable either House of Congress to exercise successfully their function."
Not so. The 1880 Supreme Court searched English common law for precedence (because absent clear case histories here, that is the proper legal source.) It found no support for the argument that Congress can coerce a witness.
‘‘We are of opinion that the right of the Houses of Representatives to punish the citizen for a contempt of its authority or a breach of its privileges can derive no support from the precedents and practices of the two Houses of the English Parliament, nor from the adjudged cases in which the English courts have upheld these practices." No support.
The 1880 court went further, saying: "Neither House of Congress was constituted a part of any court of general jurisdiction, nor has it any history to which the exercise of such power can be traced. Its power must be sought alone in some express grant in the Constitution, or be found necessary to carry into effect such powers as are there granted."
"Obstruction of Congress" (essentially they are claiming "a breach of privileges") will therefore probably be dismissed outright, under the Kilbourn decision.
The 1880 Court reiterated the inherent separation of powers between the federal departments, saying:
"The Constitution divides the power of the government which it establishes into the three departments -- the executive, the legislative, and the judicial -- and unlimited power is conferred on no department or officer of the government. It is essential to the successful working of the system that the lines which separate those departments shall be clearly defined and closely followed, and that neither of them shall be permitted to encroach upon the powers exclusively confided to the others."
"Neither of them shall be permitted to encroach". Thus, we suspect that Chief Justice Roberts presiding will so rule, citing the Kilbourn decision to this same effect. If so, you heard it here first