WASHINGTON (AP) — District of Columbia police have opened an internal affairs investigation into statements made by a police officer who responded to reports that singer Chris Brown had punched a man outside a Washington hotel.

The investigation centers on a disputed conversation between the officer and an unidentified acquaintance of Brown, discrepancies that will likely be important for the authorities to reconcile as the criminal prosecution moves forward. The apparent inconsistencies are described in charging documents laying out the basis for the assault case against Brown and his bodyguard.