I know of only two such instances in my field (law): my colleagues Brian Frye and Maybell Romero co-authored “The Right to Unmarry: A Proposal” and, pictured below, my wife and former student(!) Sydjia Robinson and yours truly co-authored a novel thought-experiment paper — published in the National Law School of India Review and available here, via JSTOR — proposing a “Unified Code of Procedure” for both civil and criminal cases!

Update #1 — I stand corrected: my new friends Carissa Byrne Hessick and Andrew Hessick have published at least 10 papers together, including this one comparing and contrasting statutory interpretation of civil versus criminal laws: “Constraining Criminal Laws“!