Of course Washington is plagued by leaks. That’s a good thing.

Let’s look back at what we wouldn’t know without leaks, bearing in mind that not all leaks are created equal. Some are document dumps; others the result of dogged reporting and the cultivation of confidential sources.

The Pentagon Papers. Perhaps the most famous leak of all, Daniel Ellsberg’s decision to copy and hand to the New York Times the secret history of the Vietnam War told Americans that thousands of young Americans had been killed fighting a war that couldn’t be won. Was it illegal for this former Pentagon official to steal and publicize the documents? Certainly, though he avoided conviction. Was there a greater good? No doubt.

Watergate. The crimes of Richard Nixon and his aides, as revealed in large part by The Washington Post, brought down the president and sent MANY government officials to jail. Was it wrong for Deep Throat, as FBI official Mark Felt was then known, to guide the investigation? Americans were better off knowing the truth.

Red Cross failures. After the 2010 Haiti earthquake, the Red Cross raised a half-billion dollars but misused the funds. NPR and ProPublica used leaks and confidential sourcing to show that an ambitious plan to build housing resulted in just six permanent homes. Congressional hearings and reform followed.