Leviticus 5:1-3

1‘Now if a person sins after he hears a 1public 2order to testify when he is a witness, whether he has seen or otherwise known, if he does not tell it, then he will bear his punishment.

2Or if a person touches 3any unclean thing, whether a carcass of an unclean animal, or the carcass of unclean cattle, or a carcass of unclean swarming things, though it is hidden from him and he is unclean, then he will be guilty.

3Or if he touches human uncleanness, of whatever sort his uncleanness may be with which he becomes unclean, and it is hidden from him, and then he comes to know it, he will be guilty.