The Spotted Dog is a pub that is located in the Whitehall area of London. It is run by Reggie and is used as a hangout for the Bethnal Green Mob.
The Spotted Dog Pub appears in the mission, Aiding and Abetting, where Mark Hammond meets Charlie Jolson and his gang to hand over the statue. Mark threatens Charlie and is hit with a bottle by Reggie. Charlie orders Mark to break Jake Jolson out of prison. The pub does not appear for the rest of the game.
The Spotted Dog still exists in The Getaway: Black Monday, although it does not appear in any missions and it is unknown who runs it in 2004. It is possible that the pub was still run by Reggie, providing he wasn't arrested after the downfall of the Bethnal Green Mob in 2002.