Hillary Clinton’s candidacy for President is widely, and aptly, described as historic. Here’s one of the reasons: If she wins, she will have spent a longer time under criminal investigation than any President in history. Why is this? Is she uniquely corrupt? Unduly targeted?

The answers are less than straightforward. The appropriate analysis, it seems, is a political riff on Bayes’s theorem. Clinton’s behavior, and the responses to it, have continued to evolve in reaction to unfolding events.

Clinton’s first experience with a criminal investigation came with Whitewater, the name given to various activities centered around a money-losing land deal that she and her husband invested in during the nineteen-eighties. Republican (and journalistic) claims of illegality in connection with the investment led to the appointment of a special prosecutor, Robert Fiske, in 1994. Fiske quickly cleared the Clintons of allegations of wrongdoing that had arisen in connection with an earlier investigation of Whitewater, as well as in the suicide of their friend and colleague Vincent Foster. Shortly after Fiske’s report, however, the court in charge of the case, under the independent-counsel law, replaced Fiske with Kenneth Starr, and Clinton’s true ordeal began.

Starr and his successors spent eight years, and more than seventy million dollars, on an investigation that began with the remains of the Whitewater probe and metastasized into an open-ended search-and-destroy mission into the personal and political lives of Bill and Hillary Clinton. Only true nineties-trivia buffs will be able to recall the full range of the accusations, which included Travelgate, Filegate, and the mystery of the missing (then found) Rose Law Firm billing records. The Clintons were pursued by a prosecutorial office fired up with political rage, but the investigation, as far as she was concerned, came to naught. The lesson she took was that Republicans used criminal investigations as a political weapon against her. In what remains her most famous utterance as a public figure, she asserted, with some justification, that there was “a vast right-wing conspiracy” out to get her family.

Starr did find pay dirt, of a sort, when he learned that Bill Clinton had lied about his relationship with Monica Lewinsky, a former White House intern, in his deposition in a sexual-harassment lawsuit brought by Paula Jones, a former Arkansas state employee, giving the prosecutor the ammunition to present evidence purportedly justifying impeachment to the House of Representatives. A bill of impeachment passed the House, but the Senate failed to convict the President, and the experience hardened the Clintons’ belief that ethics investigations existed primarily to achieve political, not legal, ends.

It was against this backdrop that the story of Secretary Clinton’s private e-mail server came to light. That Clinton would even install such a rattletrap system suggests the influence of the Starr legacy. Clinton wanted a way to shield her personal business (which was her right) while also conducting State Department business on the same e-mail account. As a Washington veteran, she should have known that such a system was fraught with peril. Most government officials avoid the problem by keeping a separate account, like one on Gmail, for private e-mail. Clinton could have done that and avoided the problems, but instead she jerry-rigged a system that supposedly could handle both personal and professional work. It was a terrible idea.

When first confronted by reports about the e-mails, Clinton reacted like a cornered perp, denying everything. She had to know (as most everyone in Washington does) that the government vastly overclassifies information, so her flat denial that there had been any classified information on her server was destined to be disproved, as it was. Retreating from that line, she said that nothing “marked” classified was on her server, and that, too, turned out to be wrong. (Not very wrong; there were just a few classification marks among her thousands of e-mails, and even those may have been mistakenly applied.) But Clinton’s visceral distaste for being the target of partisan smears led her to overreact, overdeny, and make a bad situation worse. As a victim of partisan vendettas, she couldn’t recognize a good-faith F.B.I. investigation when she saw one. But that’s what the F.B.I. delivered, in the form of a public scolding from Director James Comey (which she deserved), as well as a demurral of criminal prosecution (which was also correct).

Clinton has committed no crimes with regard to her e-mails, but she has developed an unhealthy relationship with her pursuers, who surely will only redouble their efforts if she becomes President. Burned in the past, she has become excessively defensive, and harms herself more than those who long to bring her down. The next time she’s under fire—and there will be a next time—Clinton would be best advised to forget her past and act like she hasn’t seen it all before.