• Think quickly: What do Martha Stewart (search) and I. Lewis "Scooter" Libby (search) have in common? Well, at least based on the "charges" against Libby, not a crime — but covering up a crime.

    When you obstruct justice, the idea is you are obstructing getting at the truth.

    That's why the problem for Martha wasn't that she might have sold stock in a company based on inside information — that stock sale never came up — only that she might have tried to cover her tracks long after the sale was made.

    It's the same thing that brought down Richard Nixon (search) — not a break-in into Democratic National Committee headquarters, but the administration's efforts subsequently to cover up all activity "since" that break-in.

    For Libby, the issue is whether he lied about what he did "after" the fact. Again, it's not so much whether he did or did not reveal a CIA operative's name, but if he obstructed justice by impeding the investigation into whether he did.

    I know it's confusing. But here's what is not: The crime isn't the act that gets you. It's what you did, or didn't do, after it.

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