`No, the ADL (Anti-Defamation League) and SPLC (Southern Poverty Law Center) would be considered reliable third party sources for purposes of Wikipedia. Clue: In Wikipedia, there is no requirement that the source itself be ``unbiased`` or that a source ``not make a secret of its bias.`` Please review Wikipedia rules on Neutral Point of View (NPOV). Even if these groups are ``openly anti-sovereign citizen``, that would not in and of itself be a valid objection for using the source in a Wikipedia article.     `