Champerty!

Champerty is the (largely defunct) rule against funding someone else's lawsuit. I always thought that was a funny word. Champerty. But TIL that it comes from the fact that in "England, litigants could hire ‘champions’ to represent them in ‘trial by battle.’ By the late 13th century, these strongmen were being compared to prostitutes, and their prevalence hastened the movement of dispute resolution to the courtroom. During the Middle Ages, this concept of ‘champerty’ — assisting another person’s lawsuit in exchange for a share of the proceeds — emerged as part of the larger ecclesiastical taboo against usury."