(Bloomberg Opinion) -- Even though public hearings on the impeachment of President Donald Trump have just begun, the subject has already become encrusted with legends and myths on all sides. In a polarized country, each side has its own talking points - and isn’t paying enough attention to the other side to know when those points are based on errors. So far, three stand out.Take White House acting chief of staff Mick Mulvaney’s famous remark that Trump’s critics should “get over it.” This was widely taken to be a brazen statement that it was fine for Trump to use foreign policy to seek to harm his political opponents. But that’s not what Mulvaney was saying. Nor was CNN accurate in reporting, “Mulvaney confirmed the existence of a quid pro quo and offered this retort: ‘Get over it.’”Mulvaney’s press conference was on Oct. 17. He mentioned news accounts about the previous day’s testimony from a former State Department adviser, Michael McKinley. Those reports said that McKinley had quit because he was, as the Associated Press put it, “disturbed by the politicization of foreign policy.” If you check out the transcript, you can see that Mulvaney was saying that of course politics affects foreign policy. He mentions McKinley and says: “Get over it. There’s going to be political influence on foreign policy.” Practically in the next breath, he says, “foreign policy is going to change from the Obama administration to the Trump administration.” He then faults some career government employees for seeking to prevent this.At least one reporter understood this context, because the next question for Mulvaney drew a distinction: Political influence over foreign policy is one thing, the reporter said, but is it OK for the president to try to pressure a foreign government to investigate former Vice President Joe Biden? Mulvaney then stoutly denied that Trump did any such thing, maintaining that the administration’s holding aid to Ukraine “had absolutely nothing to do with Biden.” Like a lot of what Mulvaney said at that press conference, that statement is dubious. But he didn’t admit to using foreign policy for partisan ends and then tell people to get over it.Trump supporters have myths of their own. One is the claim that in September, Representative Adam Schiff, the California Democrat who heads the House Intelligence Committee, tried to pass off a phony version of what the president told Ukrainian President Volodomyr Zelenskiy in their July 25 phone call as the actual words of the conversation. Trump accused Schiff of fraud and mused about charging him with treason: “He was supposedly reading the exact transcribed version of the call, but he completely changed the words to make it sound horrible.” House Republicans tried to censure Schiff for it, and other Trump supporters keep claiming that Schiff lied. What Schiff actually did was provide a paraphrase of Trump’s remarks, and he was completely open about it. He described how Zelenskiy opened the call and then said, “Shorn of its rambling character and in not so many words, this is the essence of what the president communicates.” Then he gave his version of the gist of Trump’s comments. After finishing, he says, “This is in sum and character what the president was trying to communicate with the president of Ukraine.” Anyone who listened to that and thought Schiff was directly quoting Trump should quit trying to follow the impeachment debate.Republicans have gotten agitated over another distorted comment recently. They say that Mark Zaid, the lawyer for the Ukraine “whistle-blower,” called for a “coup” against Trump soon after he took office. The background to this was a tweet of Zaid’s in January 2017, reacting to Trump’s dismissal of the acting attorney general, Sally Yates. Although Zaid has muddied the waters in trying to defend himself, he appears to have been saying that it was Trump who was starting to perpetrate a coup. It was a dumb tweet: Trump was well within his rights to fire Yates, who had refused to defend his travel ban. But it doesn’t support the Republican case that Ukrainegate is an undemocratic plot by Trump’s enemies.All of these mangled and misunderstood remarks are, in a sense, peripheral to the main debate. Whether Trump should be removed from office shouldn’t turn on a three-year-old tweet from one government employee’s lawyer. Each of these exaggerated stories is, however, helping to create an atmosphere in the minds of fans and foes of the president. Each side can not only interpret events in keeping with its favored narrative - Trump’s corruption or deep-state plotting - but also tell itself that the other side secretly knows it’s wrong.People who are following the impeachment hearings and trying to make up their minds should read and listen to both sides, carefully. It’s not just that each side is trying to spin the facts. It’s that each side is spinning itself.To contact the author of this story: Ramesh Ponnuru at rponnuru@bloomberg.netTo contact the editor responsible for this story: Tobin Harshaw at tharshaw@bloomberg.netThis column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.Ramesh Ponnuru is a Bloomberg Opinion columnist. He is a senior editor at National Review, visiting fellow at the American Enterprise Institute and contributor to CBS News.For more articles like this, please visit us at bloomberg.com/opinion©2019 Bloomberg L.P.