ANOTHER ILLUSTRATION OF THE FREE SPEECH PRINCIPLE THAT THE GOVERNMENT CANNOT DISCRIMINATE BASED ON VIEWPOINT

Tax exemptions are another example of an area where the government can’t discriminate because viewpoints expressed by some exemption recipients may be disfavored.  To put it another way, if the government grants a tax exemption to a particular category of entity, the government cannot then deny that exemption to entities that are within the category but that express views that are objectionable.  Even if those views are, for example, racist.  
For an excellent discourse on the application of free speech jurisprudence to the granting of tax exemptions, I encourage you to read the recent testimony on the subject by Eugene Volokh before the Oversight Committee of the House Ways & Means Committee.  He does a great job of explaining why it’s so important that free speech principles be applied correctly in tax administration.