In The Dark Knight,
Jim Gordon is apparently killed in the line of duty.
When the city calls for Batman to be arrested, Harvey Dent turns himself in as Batman before Bruce has a chance.
During transport, the Joker and his men attack the transport. When the Joker is apprehended, it is revealed that
Jim Gordon is not only still alive, but that he was the driver of the truck transporting Harvey Dent. The conversation between Dent and Gordon indicates that Dent seemingly had no idea of Gordon's plan.
Dent: You DO like to play things close to the chest.
It is also revealed at this point that
Gordon's family did not know about the ruse.
The most obvious answer is that Batman and Gordon came up with the plan, but Bruce had originally intended to turn himself in.
Who was involved in this plan, and what was the original plan (when did Gordon intend to reveal the truth)?
Specific points to consider:
- The police were attempting to prevent any fatalities at the funeral. He had no way to know who else might be attacked there. If events hadn't unfolded exactly as they did, this plan could never be put into motion. (h/t to Deion for pointing this out.)
- No one seemed to expect Dent to turn himself in.
- While the convoy attack wasn't completely unexpected, there was no guarantee.
- If Bruce had turned himself in, Batman would not have been able to assist defending the convoy attack.
- It is only because the Joker was apprehended that Gordon's plan could be revealed.