Saying that something doesn't pass the giggle test is a colorful way of saying that it is utterly ludicrous.
of this phrase is presented in the PETITION FOR WRIT OF MANDAMUS AND/OR PROHIBITION AND/OR FOR A DECLARATORY RULING
to the Supreme Court
of the State of Missouri
The giggle test is when the common person on the street hears this opinion, and the conduct of this court in refusing to sign orders, it causes them to giggle, roll their eyes, and exclaim, "you gotta be kidding me!"