(b) Whoever knowingly uses intimidation, threatens, or corruptly persuades another person, or attempts to do so...

(b) Whoever knowingly uses intimidation, threatens, or corruptly persuades another person, or attempts to do so, or engages in misleading conduct toward another person, with intent to—
(1) influence, delay, or prevent the testimony of any person in an official proceeding;
(3) hinder, delay, or prevent the communication to a law enforcement officer or judge of the United States of information relating to the commission or possible commission of a Federal offense or a violation of conditions of probation
Possible violations:
B1 - Firing of Comey (intimidation), tweets to Sally Yates before her testimony, tweets threatening Comey about "better hope there are no tapes" (threatens), Demanding absolute loyalty (corrupt persuasion) (Both: influence, delay, or prevent testimony), asking the NSA director if they could shut down the FBI investigation (Corruptly persuades). All these require are "attempts",
B3 - "I hope you can see your way to letting this go" (prevent the communication to a judge of information relating to the commission of a federal offense),
Misleading conduct: Inviting Comey to a dinner on false pretenses.
add: Threatening to fire Mueller if he looks into Trump family finances, as this would have the effect of hindering communication of possible commission of a Federal offense.
(d) Whoever intentionally harasses another person and thereby hinders, delays, prevents, or dissuades any person from—
(4) causing a criminal prosecution, or a parole or probation revocation proceeding, to be sought or instituted, or assisting in such prosecution or proceeding; or attempts to do so, shall be fined under this title or imprisoned not more than 3 years, or both

Possible Violations
D4 - Multiple meetings that lead to an FBI director taking memos (intentional harassment), threatening Comey on twitter (intentional harassment), demanding loyalty (intentional harrassment)
add: Threatening to fire Mueller if he looks into Trump family finances, as this would be a clear dissuasion from causing a criminal prosecution to be sought or instituted.

Things that show intent:
Telling Russians that firing Comey "relieved a great pressure on the Russia thing"
Asking others to leave the room during one of the meetings
Asking Mike Rogers and Dan Coates if there was anything they could do to end the investigation
Inviting Comey under pretense that others would be at the meeting and then nobody was there
Directly asking if Comey could "see to letting these things go"
The FBI director's own judgement
Trump was thinking of the Russia investigation when he fired Comey.
add:: Saying in the NYT interview that he wouldn't have hired Sessions if he knew he'd recuse himself.
Other important parts of this statute:
(e) In a prosecution for an offense under this section, it is an affirmative defense, as to which the defendant has the burden of proof by a preponderance of the evidence, that the conduct consisted solely of lawful conduct and that the defendant’s sole intention was to encourage, induce, or cause the other person to testify truthfully.
This shows that the law is broad and gives Trump little wiggle room. The burden of proof is entirely on him to show that his actions were solely to get someone else to testify truthfully.
(g) In a prosecution for an offense under this section, no state of mind need be proved with respect to the circumstance— (1) that the official proceeding before a judge, court, magistrate judge, grand jury, or government agency is before a judge or court of the United States, a United States magistrate judge, a bankruptcy judge, a Federal grand jury, or a Federal Government agency; or (2) that the judge is a judge of the United States or that the law enforcement officer is an officer or employee of the Federal Government or a person authorized to act for or on behalf of the Federal Government or serving the Federal Government as an adviser or consultant.
This expands the statutes away from just a "judge" and also has them apply to federal government agencies.

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Your benefactor is doomed

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