constitutional insubstantiality

Constitutional insubstantiality' for this purpose has been equated with such concepts as 'essentially fictitious,' 'wholly insubstantial,' 'obviously frivolous,' and 'obviously without merit.' The limiting words 'wholly' and 'obviously' have cogent legal significance. In the context of the effect of prior decisions upon the substantiality of constitutional claims, those words import that claims are constitutionally insubstantial only if the prior decisions inescapably render the claims frivolous; previous decisions that merely render claims of doubtful or questionable merit do not render them insubstantial for the purposes of 28 U.S.C. § 2281. A claim is insubstantial only if 'its unsoundness so clearly results from the previous decisions of this court as to foreclose the subject and leave no room for the inference that the questions sought to be raised can be the subject of controversy.

Defined by the Supreme Court in - Goosby v. Osser, 409 U.S. 512 (1973).