Order in the court! (OSR legal argument rules)
So your PCs have gotten themselves in trouble with The Law, but rather than just presumed guilty and tossed in a prison cell or executioner's block (presumably for a dramatic escape, or possibly just to show them that actions have consequences), they're dragged into a courtroom and forced to argue for their own innocence. How do they get out of this alive? Let's find out...
For Glaugust challenge 4: system for legal arguments in a court of law. Is it good? Who knows. Inspired partly by the trial of Neverwinter Nights 2.
The Basics
This system is based on Occultronics' social resolution rules. The goal of a trial, in simplest terms, is to convince the judge(s) and/or jury that the case should be resolved in your favor. The prosecution and defense present their arguments, each of which must be based on a witness or piece of evidence, and the PC doing the arguing (or lawyer NPC being run by one of the players) rolls 2d6 plus applicable modifiers vs the target number. The baseline is as follows:
- The base target number is 8. Adjust up by 2 if the opposition has/is someone trained in law and the PCs have neither the skill nor someone else who does, lower by 2 if the reverse.
- Arguments brought up by the PC side give +1 point on a success, while arguments brought up by the opposing side give -1 point on a failure.
- Whoever is arguing applies the difference between their best mental stat and that of their opposition as a bonus or penalty. Assume NPC lawyers have a +1 in their best stat, +2 if exceptionally intelligent/charismatic (these lawyers are usually foreshadowed in advance).
- Arguments based on a witness involve interacting with and pressing them. Most modifiers that would apply here (as seen in the Persuasion section of the above link) can only be used by talking with the witness prior to the trial, and less than savory modifiers like threats can be inverted into penalties if the court finds out about them. The obvious exceptions are inherent biases for or against one side (treat at a +/-1), which either apply by default or can be brought up in-court, and new information, which is covered under Evidence. Assume any witnesses brought in by the opposing side already have 1-2 points worth of modifier applied as a penalty to your roll. Any witnesses for the PCs will almost certainly be available for convincing prior to the trial, potentially along with opposing witnesses as well.
- Evidence can be used as a modifier in witness arguments or to start an argument in itself. if the evidence is substantial and in your favor, you have a +1 to the roll. If the evidence is used in a witness testimony and directly proves or disproves their statement (as relevant), it grants a +3/-3 instead and can reverse the argument instead of merely disproving it (which allows the PCs to gain points on an opposing argument, for instance). Evidence can only be used once each, after which it cannot be brought up again unless extremely relevant to a witness testimony. Evidence is, of course, gathered prior to the trial.
- If an argument seems especially relevant to the case (e.g. nigh-irrefutable proof that the PCs could not have been present at the crime scene), then it could be worth 2 or even 3 points.
- The PCs may take a stacking -1 penalty to all future rolls in this trial to reroll an argument.
- At the end of the trial, assuming only one judge or unit of judges, the ruling is decided in favor of the PCs if their total is positive, and against if the total is negative. On a tie, rule for the prosecution unless the system is explicitly and genuinely operating under innocent until proven guilty.
Legal System
There are many legal systems, though obviously your PCs are in one that has a court system in the first place if you're using these rules. These can just be cultural biases, which can be used to inform the biases of the judge and jury, but sometimes a bias is baked into the laws themselves, in which case you should treat the PCs as starting with a free success if benefiting from a codified bias or an automatic failure if working against one.
Judge and Jury
A given court will always have at least one judge and potentially a jury. If there are multiple judges and no jury, they will either act as a single unit or there will be an odd number to prevent ties. Judges and juries can have their own biases, which adjust their target numbers by one in the appropriate direction, and these are allowed to differ. This does mean that a roll can fail against one judge but succeed against another. Biases can stack. Juries can safely be assumed to have whatever biases their composing demographic has as a whole. Additionally, sometimes a judge or jury is out for blood and simply wants a conviction, in which case the target number should adjust by one in favor of the prosecution.
As with witnesses, the judge and jury can be bribed or sweet-talked before the trial to adjust their target numbers down. Note that the jury acts as a unit and must be somehow convinced collectively, while judges tend to be at least of merchant class or higher, so bribes and threats must be sufficient for someone with political clout. Some judges may be especially honest and truth-focused, which renders these methods moot but gives evidence an extra +1 bonus.
If the judge(s) and jury disagree, the ruling depends on the system. Some treat the judge as nothing more than referee and tiebreaker, in which case their opinion only matters if the jury's final score is 0. If the judge has some power but is subordinate to the jury, then a disagreement will likely involve the judge lightening the sentence or finding some legal means to punish the defense anyway, as appropriate. If, conversely, the "jury" is essentially just a collection of spectators, then a disagreement will result in the judge's verdict going through against public outcry. This could lead to the PCs being treated better or worse by the local citizens after the trial regardless of verdict, as is appropriate, or in the case of the PCs being convicted against the jury, even rescued from their cell before execution by NPCs.