I really haven't been able to find much info about them, and I've spent quite a while googling around...
This is part of what Wikipedia says:
Criticism of the ISHR's role
In Germany, its main stronghold, the ISHR-IGFM is subject to controversy and strong criticism. Prominent members of the society are known to have publicly endorsed the death penalty as well as hailed Chile's former dictator Augusto Pinochet. Further accusations include ties with the Korean Moon sect (Unification Church).
Critics say that the ISHR typically does not bother about human rights violations as long as governments responsible for them share the strictly anti-communist convictions held by the organisation. This means that the ISHR disregards the universality of human rights, which is one of the fundamental aspects of human rights protection. Consequently, the ISHR's reputation as a human rights organisation is significantly lower than that of organisations such as Amnesty International or Human Rights Watch.
http://en.wikipedia.org/wiki/International_Society_for_Human_Rights