The Court of the Republic, which deals with cases involving suspected misconduct by sitting cabinet members, launched the probe following complaints by Anticor, an anti-corruption association, and three magistrates' unions.
The allegations centre on an administrative investigation ordered by Dupond-Moretti against three prosecutors working at the financial crimes prosecutor's office.
The three were part of a team trying to find a mole who may have warned former president Nicolas Sarkozy and his lawyer Thierry Herzog that their phones were being tapped as part of a corruption probe.
The investigators checked the phone records of, among others, Dupond-Moretti, who was still a criminal defence lawyer at the time and not yet a minister, and who filed a complaint against them.
Asked last week about the allegations that he may have used his cabinet job to settle scores, Dupond-Moretti said: “When the time comes I will explain myself, you can count on me to say everything that I have to say”.