The friends are warned in strongest terms against reading the literature of Covenant-Breakers

...the friends are warned in strongest terms against reading such literature because Covenant-breaking is a spiritual poison and the calumnies and distortions of the truth which the Covenant-breakers give out are such that they can undermine the faith of the believer and plant the seeds of doubt unless he is forearmed with an unshakable belief in Bahá'u'lláh and His Covenant and a knowledge of the true facts.

https://bahai-library.com/uhj_covenant_breakers_history