Marvin Branagh is a lieutenant in the RPD.
In the original Resident Evil 2, he is discovered suffering from a serious injury in Scenario A by either Leon Kennedy or Claire Redfield, and informs them of the Mansion Incident. Giving them his keycard to unlock areas of the police station, he forces them to leave him behind and locks the door behind them. Marvin later transforms into a zombie and attacks the player.
In the Resident Evil 2 remake, he is more proactive in helping the protagonists escape the RPD and helps them unlock the passage before also becoming a zombie when the player returns to the RPD.
Marvin also appears briefly in both versions of Resident Evil 3: Nemesis, the remake showing that he was infected by a zombified Brad Vickers.
Marvin also appears in Resident Evil Outbreak: File 2 and Resident Evil: The Darkside Chronicles.