Jury selection starts today in the trial of former presidential candidate John Edwards on six felony charges of federal campaign finance law violations involving an alleged conspiracy and the making of false statements. Despite the mountain of evidence that they claim backs up these allegations, the prosecutors’ main weapon in the trial will be the fact that Edwards is generally held to be among the most repulsive politicians to stride across our national stage in a generation. He is a vain, puffed up politician who was always something of a fraud even in his heyday. He is also a liar who cheated on his terminally ill wife and did everything possible to deceive the public about his affair and the child he fathered with his mistress. But that’s also the problem with this case. Absent Edward’s reputation as bottom-feeder, there is no way that any prosecutor would seek to bring anyone else to court on such flimsy charges.

The irony here is that although John Edwards is the quintessential sleazy politician who has earned the public’s scorn, his trial will actually be a crucial test of a key principle: Whether the Justice Department can interpret the byzantine and vague campaign finance laws so as to treat virtually anything a candidate gets as an official contribution that can be regulated. The case illustrates a fundamental principle of the legal system that demands that even the most loathsome of citizens deserves the same protections and rights as the most righteous. Though Americans may well think Edwards deserves a possible sentence of up to 30 years and $1.5 million in fines for his reprehensible conduct toward his late wife, he must be acquitted if we are to prevent the government from assuming more power that it could use against worthier citizens.

John Edwards is an easy man to despise. His treatment of his wife and family and friends was awful. But these are private failings. The willingness of the press to avoid coverage of his personal conduct while he was a viable contender for his party’s presidential nomination was the real public scandal here.

There’s no question that Edwards behaved immorally by arranging for two wealthy friends and supporters to provide money for his mistress so his wife wouldn’t discover his affair. But the money given to Rielle Hunter, the equally sleazy campaign videographer who gave birth to Edwards’ child, was not a crime in the sense of the word that we normally use when discussing the court system. Gift taxes were paid on the money that was not funneled through Edwards’ presidential campaign accounts. The government’s attempt to treat this arrangement as an illegal campaign contribution for which he can be sent to jail for decades is an unprecedented attempt to expand the scope of laws that already require candidates to hire lawyers just to understand.

While the Justice Department will attempt to treat this case as the unraveling of a criminal conspiracy, what they are really doing is capitalizing on a tabloid scandal. The only reason Edwards is on trial is because he is a rich, famous and extremely unpopular person. Ambitious prosecutors believe they can convince a jury that is likely to view Edwards with as much disdain as the rest of the country that because his behavior was wrong and money was involved, that it was somehow a criminal affair.

What they are doing here is a classic case of prosecutorial overreach in which the government attempts to criminalize conduct that is worthy of censure but doesn’t actually constitute a violation of the law. Even worse, by expanding the reach of campaign finance laws, a guilty verdict against Edwards would strengthen the ability of the government to criminalize virtually any aspect of a candidate’s life. In the hands of unscrupulous officials, these laws could become a weapon to use against political enemies in a manner that could place even the most ethical politicians in the dock. Rather than give the government more power over this sphere, we need to pare back the byzantine maze of regulations.

John Edwards may well be the epitome of all that is wrong with American politics. But his prosecution symbolizes everything that is corrupt about the justice system.