- Hans Kelsen, of Jewish upbringing, briefly convert to Catholicism, then apostasised to Augsburg Confession Evangelisch (=Lutheran)
- Georg Jellinek, also of Jewish upbringing, not strictly Halakhic.
- Félix Somló - again of Jewish heritage, and in this case finished a suicide.
One can somehow understand why Jews would be legal positivists. There is no direct reason in the natural law for forbidding pork or tissue mixed* from wool and linen ... however, we Catholics consider these bans related to natural law in a special application for the Old Testament. But as they were not Catholics, they did not understand the Torah./HGL
* There is no ban on clothes sewn from two different tissues or on wearing two different pieces of clothing each in one of the tissues, there is a ban on mixing warp in one and weft in other. Or was. It really is a ban on mixing Christian truth with Pagan falsehood, as the heretics do.