I don't think the media is emphasizing enough that the inquiry consists of three house committees. each of the three committees has Republican members, and each of them by themselves has the power to subpoena.
there have been Republican members asking questions during each of these depositions.
so the powers are legitimately derived, and the Republicans have an opportunity to participate in the process.
if Matt Gaetz wanted to participate he should have got himself appointed to a different committee.

If you think this is all a waste of time by Democrats that's your right. Vote accordingly in the next election. But what the Democrats are doing is totally within the rules and precedents. Trying to bring a foreign government into the employ of a US political party is not. The Democrats are accusing Trump of this, and it is very serious. As they are the majority party in the house right now, they deserve an opportunity to do a thorough investigation so that they may prove this, or fail to prove it if the evidence is not there.

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