After three days of "why" came the "why not." President Trump's legal team took their turn before the Senate on Saturday to rebut Democrats' lengthy arguments for removing Trump from office. Why it matters: Today's two-hour session was a first look at Trump's defense. The Trump team methodically tried to poke holes in the House impeachment managers' case, rather than going after the Bidens, as they previously suggested they will.Trump's defense team noted during two hours every bit of evidence they say the managers skipped, trying to cast doubt whenever it could on linking Trump's requests to investigate the Bidens to delaying military aide to Ukraine.The Senate proceedings will resume at 1 pm on Monday.Highlights: Trump lawyer Jay Sekulow held up a copy of the Mueller report and noted, "'ultimately' -- these are the words of Bob Mueller in his report -- 'this investigation did not establish that the campaign coordinated or conspired with the Russian government and its election interference activities.'"Context: The Mueller investigation established multiple links between Trump campaign officials and people tied to the Russian government — including Russian offers of campaign assistance that the campaign was occasionally receptive to.Trump deputy counsel Michael Purpura pointed to testimony from Bill Taylor, George Kent, Kurt Volker, and Tim Morrison to argue that Ukrainian officials did not know key military aid was withheld at the time of Trump's infamous July 25 call with Ukraine's president, so withholding aid could not have been a threat. Between the lines: Ukraine's former deputy foreign minister Olena Zerkal told the New York Times that Ukraine's government was aware of the Trump administration's decision to freeze military aid in July.Context: Emails released to the Center for Public Integrity show the OMB ordered the Pentagon to withhold military aid to Ukraine 91 minutes after Trump's phone call with Ukrainian counterpart Volodymyr Zelensky.White House counsel Pat Cipollone opened Saturday's session by accusing House Democrats of hiding evidence from the Senate and framing the historic decision to impeach Trump as taking away voters' ability to judge the president for his actions.The mood in the chamber: Of the five Republicans who are being watched most closely as possible votes for witnesses, Sens. Susan Collins, Lisa Murkowski, and Cory Gardner were the most prolific note-takers.Of the Democrats seeking the White House: Sen. Bernie Sanders sat slumped at his desk, resting his chin on his hand or fidgeting with his fingers clasped in front of his face.Sen. Elizabeth Warren sat hunched over a legal pad for a long time, writing furiously and not appearing to pay attention to the trial.Sen. Amy Klobuchar took some notes and watched some of the Trump team's remarks, but often looked away and stared around the room.The other side: Democratic House impeachment managers marched 28,578 pages of impeachment trial and witness records to the Senate on Saturday morning. Reps. Mark Meadows (R-N.C.) and Elise Stefanik (R-N.Y.) meet with reporters before Saturday's session of the Senate impeachment trial. Photo: David Nather.What you need to know:Trump-Ukraine scandal: The key players, dates and documentsFact check: What Joe and Hunter Biden actually did in UkraineThe highlights from all of the public impeachment hearingsGo deeper:What deserves your attention during the impeachment trialThe daily highlights from Trump's impeachment trial