In the DC Comics, Peña Duro is a prison on the island of Santa Prisca and is best-known as the place where the supervillain Bane spent most of his life. Due to unknown reasons, the name was slightly altered for the location's appearance on Gotham.
The title is Spanish for "Hard Sentence."
The black and white film the arms trafficker was watching, was a film noir classic called Tangier Incident (1953). Incidentally, the protagonist of the film is called Steve Gordon (no apparent relation to Jim Gordon).
One of the names on the arms dealer's ledger seems to resemble the name Ben Edlund. Edlund was an executive producer and writer for Gotham.