There isn't a legal justification for treating them differently than other groups that advocate for various issues (as opposed to for candidates, which is not exempt). Planned Parenthood is exempt -- so is the Culture of Life Fund.
http://www.kofc.org/un/index.cfmCulture of Life Fund
The Supreme Knight addressed the 2008 Annual Supreme Council Meeting saying, “Today we constantly hear about change. We must remember that real change means building a culture of life and a civilization of love.” He continued, “We are a non-partisan organization, and Knights belong to a variety of political parties. We do not endorse candidates for public office, although many of our members are elected officials. But we do take a strong interest in certain critical issues that affect our most fundamental values as Catholic Christians and as citizens…. And if we truly hope for a Culture of Life and a Civilization of Love, then we must first think, and then act, in new ways.“
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If we are determined in our commitment to build a Culture of Life, considerable resources will be necessary. That is why we are encouraging contributions. The funds will be accumulated by country and used in that country in matters affecting life, family, marriage, and similar priorities in building a Culture of Life.
Please help us through your prayers and donations as we endeavor to build a Culture of Life.
To the extent permitted by law, your gift is tax deductible in the United States or tax creditable in Canada.
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