Generally, for flashback usage, I would assume that it starts from somewhere near the end, but this one creates a twist right before when everyone thought it could come to an end. Very clear, and gives much surprise to me, and many other audience as well I believe.
It's a bit sad that the actress didn't make it to the end.
It's quite ingenious to only highlight the title in the very end.
One doubt: close to the end, the police officer called the senator, but the senator shouted to him, and hanged up on him. This scene feels rather odd to me.