Halakhah sobre Bechorot 4:13

The reason for this is straightforward: as the Mishnah (Bechorot 4:10) records, “One who does not observe a particular mitzvah cannot serve as a judge or witness regarding that mitzvah.” For example, one cannot trust the kashrut of someone who does not abide by the laws of kashrut. One who does not observe a Torah law sometimes cannot psychologically grasp the importance of observing that law meticulously. An archaeologist who does not observe Torah law might not be sensitive to the importance of the great dignity with which Halachah requires us to treat the dead.