What Is the Connection Between Anthony Pellicano And the Clintons?

The Guardian reports:

Pellicano did work directly with one president: during Bill Clinton's first presidential campaign Pellicano was hired, reportedly by Hillary Clinton, to discredit Gennifer Flowers, the woman who alleged that she had maintained a 12-year affair with the candidate. Six years later, with Clinton into his second term, the White House, according to the New York Post, hired Pellicano, considered a respected forensic audio specialist, to look into Monica Lewinsky's background.

Are these facts or accusations? If they are facts we'd like to hear what Hillary Clinton has to say on the growing subject of Pellicano.