In 2002, various news sources reported that a red heifer was found and the Temple Institute in Israel declared it kosher. Many of these sources later reported that the parah aduma was disqualified ...
Let's say I use the pretty much disproven Techelet (Radzyner) : is my Tzitzit completely Pasul? I think according to the Arizal it isn't. Does anyone disagree?
If someone comes up to daven as a chazzan, and you have questions about how kosher they are or whether they're truly shomer shabbos, are you allowed to still use him as a chazzan, or are there ...
May a child make a Berachah on a Pasul set of 4 species that their parents gave them to learn how to make the Berachah and do the Mitzvah?
If someone built a Sukkah large enough to enclose a tree, but not more than 20 Amoth tall, may someone sit under that tree on Sukkoth?
People who participate in certain activities that are bad for society are disqualified from testifying. Also, those who've commit certain sins whose punishment is corporal, and haven't yet repented, ...