As a child, Lloyd was somewhat traumatized by some of the scarier moments in classic Disney films and, by playing Judge Doom, he believed he could have a little payback. This was ever so present in one of Doom’s most cruel scenes, which is ironically one of Lloyd’s favorites.
Article source: https://www.cinemablend.com/news/2495559/why-christopher-lloyd-never-blinked-while-playing-his-who-framed-roger-rabbit-character