Most important rule of GM-ing, do not over-prepare details, keep a vague outline and let the player figure out the details.
At best, the PC will just find another solution that the one you ignore (why fight the guard when you can bribe/blackmail them) or even they'll ignore huge part of your scenario.
Tiens d'ailleurs, quand tu es condmanable à une peine de prison, tu as le droit de quitter le tribunal avant le jugement ? Il se passe quoi si le juge t'envoie en zonzon et que tu es pas là ?