Because the hearings are not a court of law presided over by a judge, Republicans can disrupt to their heart's content. They did a great job of it, and the Democrats a poor job.
Lewandowski stonewalled all day, although the Democratic council at least demonstrated that he was a liar.
Lewandowski's stonewalling makes it easy to find him in contempt of Congress, and he should be found in contempt. He has no standing to stonewall, the president's meaningless instructions notwithstanding. The president is simply contemptuous of the Constitution, but that has been the case in several respects through his term to date.
Nonetheless, Lewandowski must have known he could be contemptuous of Congress to the max, because he knows Barr is the AG. With Barr as the AG, the Dept. of Justice will never charge Lewandowski with contempt. Like Trump, AG Barr cares not a wit for our Constitution. As long as Barr is the AG, he will act as the president's attorney and protect Trump.
With Republicans doing a better job of gerrymandering, and a better job of voter surpression, and with the Electoral College ensuring that 65% of close presidential elections will be won by Republicans, despite losing the popular vote in such elections, and with the Supreme Court possibly moving even further right should Trump obtain another choice for the SCOTUS, an increasingly diverse nation, caught in the grips of tribalism first, country last, we will likely move closer to a single party state, practically speaking, not literally, as, increasingly, Democrats will seldom hold the Senate or the Oval Office. With the Republicans packing the lower courts with conservative justices, even as the country becomes more diverse, and even as the culture wars pit progressives vs. reactionaries, we should see continued social strife for generations to come.
And if that's where we're heading, well, good luck with that, America....