I am writing an adventure where the PCs need to win a prisoner's freedom. It is taking place in the Shackles. A pirate is accused of a crime and the prosecuting party has hired a famous cut-throat lawyer from Hell Harbor (who is both a cut throat and a lawyer) to represent him. There is no chance that the pirate will be found innocent because of this. I would like this to be resolvable by the PCs "Seeking Besmara's Judgment", which means trial by a duel. The pirate picks one of the PCs and the lawyer represents his side.
I hoped to use the duel rules from Ultimate Combat. My question is, what are some ways I can give this lawyer some advantages, which using tricks and cleverness the PCs can negate? They will be level 1 or 2 when they do this.
One thing I wanted to do was give the lawyer a high chance of threatening and confirming crits, but also using Jerrin the Jinx from Campaign Setting: NPC Guide as the imprisoned pirate. If the PCs can arrange to have him nearby, he has an innate, passive ability to nullify critical hits. What are some ways that I can up his critical threat? I can't really have him be higher than level 2 or 3, and most of the feats that apply to crits would be out of his reach. I know there are some traits that can help a little. Also, I had thought about giving him a rapier with oil of keen edge applied to it for a 15-20 threat range without the chance of a potent magic item falling into the hands of low level PCs.
Can you think of anything else I might do? Also, any other advantages the PCs can surreptitiously give themselves that might help? This isn't a duel to the death, just until the other side yields.