Transcript for Kavanaugh is sworn in as Supreme Court justice

the political storm moving across the country. Judge Brett Kavanaugh sworn in, and tonight, what Susan Collins is saying about the allegation of sexual assault. Here's Tara Palmeri. Reporter: Newly sworn in justice Brett Kavanaugh ready to take his seat on the high court. But still facing a divided nation of angry protests and fierce opposition. A prominent congressional Democrat threatening to open an investigation into the accusations of sexual misconduct and perjury if their party wins back the house in November. President trump accusing the Democrats of playing politics. Democrats have become too extreme and too dangerous to govern. Republicans believe in the rule of law, not the rule of the mob. Reporter: Republicans hoping the battle over Kavanaugh will ignite the base and stave off a blue wave in the midterms. So I want to thank -- I want to thank the other side for the tactics that have allowed us to kind of energize and get involved our own voters. Reporter: Lawmakers on both sides already feeling the political backlash. President trump told "The Washington post" that Republican senator Lisa murkowski of Alaska will, quote, "Never recover" for siding against Kavanaugh and will lose her senate seat in 2022. I thought it was frankly disgraceful. I've done so much for Alaska, I was shocked to see her vote. Reporter: Democrats may also target moderate Republican senator Susan Collins of Maine, who cast a crucial vote for Kavanaugh. I do not believe that Brett Kavanaugh was her assailant. I do believe she was assaulted. I don't know by whom and I'm not certain when. Reporter: Kavanaugh, a known conservative, shifts the court's balance. Something then candidate trump pledged would lead to a change in abortion law. Do you want to see the court overturn roe V. Wade? Well, if we put another two or perhaps three justices on, that's really what's going to be -- that's, will happen and that'll happen automatically, in my opinion, because I am putting pro-life justices on the court. Reporter: But senator Collins says Kavanaugh told her the law won't change. Does the president now expect that we are going to see roe V. Wade overturned? Both justice Gorsuch and justice Kavanaugh, in their respective supreme court hearings, nomination hearings, excuse me, said that roe is settled law. Tara, justice Brett Kavanaugh will start hearing cases as early as this week. He's already ruling on some hot button issues? Reporter: That's right. Tuesday, he will have his first day on the high court. He'll hear cases on guns and immigration. But before that, he will be at the white house for a swearing-in ceremony. Tom? Tara, thank you.

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