This is an impeachable crime and Speaker of the House; Paul Ryan is obstructing justice by failing to take actions to impeach him. Furthermore, Speaker Ryan has actively protected and defended Trump while evidence points to his campaigns colluding with Russians to disrupt the Clinton Campaign.
Essential is understanding the relationship between Trump and his company and Russians. That is the subject of alleged Emolument Clause violations that demand a full inspection of his tax records by the FBI in concert with the Treasury and IRS.
Combine what is known from the National Intelligence Service, there is sufficient evidence to pursue an avenue toward impeachment.
Misprision of Fraud is already something that can be proven and understood by average Americans. Trump lied about Mike Flynn. Flynn was an unregistered foreign agent, paid by the Russians when Trump nominated him to National Security Advisor. The Republican Senate rubber stamped Flynn, and that was a dereliction of duty and professional irresponsibility for which the participants must be held accountable.
The splashback from all of this is on the Republican Party and the incumbents who are up for reelection.
Lying by a federal government official is a crime. Trump has lied many times including having made false allegations against the former President. That alone is sufficient to render him and his administration illegitimate.
Now, Paul Ryan's actions require that he recuse himself, and step down as Speaker of the House.
"Joe’s tough message to Republicans
Joe Scarborough talks about the firing of James Comey and warns Republicans, that "the President is subverting the U.S. constitution, ‘If you allow this to go unchecked, you will be swept aside in 2018.”