RALEIGH – John Edwards’ lawyers have just filed what the Raleigh News & Observer describes as a “barrage of court documents” challenging the prosecution of their client on campaign-finance charges.

The lawyers argue that the federal government’s case is based on an untested, unreasonable legal theory that would, if accepted by a court, render it virtually impossible for a political candidate to have a private life. “The distinction between a wrong and a crime is at the heart of this case,” the lawyers wrote.

As far as I can tell, they are absolutely right. Former U.S. Attorney George Holding and the career prosecutors should never have charged the former senator with the “crime” of accepting gifts from friends to pay for his mistress. As disgusting as John Edwards’ behavior was, it cannot reasonably be considered a crime.

What is undeniable is that Edwards had an affair with Rielle Hunter, that she later give birth to his daughter, and that friends of Edwards who were also political donors made sizable monetary gifts to support Hunter and the child.

The prosecution argues that these relationships amount to a criminal conspiracy to evade campaign-finance laws by keeping Hunter satisfied and quiet so she wouldn’t go public and destroy Edwards’ candidacy. The problem is that even if Edwards hadn’t been a presidential candidate, he would still have had compelling reasons to keep Hunter quiet, such as keeping his dying wife in the dark and avoiding public embarrassment. Similarly, close friends of Edwards may have been inclined to help him with Hunter even if there was no political implications.

Remember, you don’t have to like Edwards and his pals or condone their behavior to be worried about government overreaching here.

To show that Edwards committed a crime, prosecutors would have to establish that the gifts amounted to illegal, unreported contributions to his political campaign – and that he and his friends intended to evade the campaign-finance laws. Unless there is some real evidence of such a conspiracy – documents or testimony from Edwards’ friends – I don’t see how the prosecution can meet their burden.

To accept the government’s theory of the case would be, as Edwards’ attorneys argue, to erase “any distinction between a person’s candidacy and his private life.” All sorts of private transactions between a candidate and his friends or family members could be construed as helping him run for office, even if their primary and intended effects weren’t political.

Even politicians seeking the highest office in the land have the right to maintain a private life without fearing criminal prosecution.

That doesn’t mean, of course, that their fellow citizens have no right to inquire about that private life. And in a free society, one should always have the right to publish true, legally obtained information about a candidate’s private life.

Private behavior doesn’t have to be criminal to be germane to a candidate’s fitness for office. Would-be presidents who abuse alcohol or other drugs, manage their finances recklessly, or repeatedly cheat on their spouses don’t strike me as well suited to the job. I doubt they would be able to handle the pressure, and might be vulnerable to distraction, undue influence, or blackmail.

Still, turning a sordid scandal into a federal crime requires more evidence and a better argument than federal prosecutors seem to able to muster in the John Edwards case. I’m not saying that “the man has suffered enough” or anything like that. I don’t know enough about him to make that judgment.

What I do know is that criminal law is a blunt instrument and not always suited to the task of policing immoral or idiotic behavior.

Hood is president of the John Locke Foundation.