On Mission 14, any glass broken in Mission 13 is unbroken.
In the lighthouse elevator, rain is falling, even though it is completely indoors.
Bug: Hostile NPCs that have been incapacitated sometimes talk after incapacitation.
Soldiers and guards are always seen with their swords drawn. Most swords are too heavy to be constantly carried, and are thus put in their scabbard until needed.
It is possible for the Player to activate objects or fire arrows in front of NPCs, which should not be possible.
The record players have musical disks instead of records. Musical disks cannot be played by record players.
Underground areas are not well-ventilated enough to be habitable.
During the mission to the police station, the Player is given the option to steal from the police station. By any logical train of thought, this should arouse suspicion and make Garrett's mission meaningless.
In Mission 13, the Player is tasked with searching through a mansion without letting anyone know he is there. In spite of this, the Player is still allowed to steal objects, which it should follow would be missed.
The items that can be purchased at the store are more expensive than the loot that can be obtained on a mission, which would make each mission ultimately not worth it.
In Mission 13, the construction foreman states that she misplaced a toolkit - even though the toolkit is in plain sight not far away.