Typically if the trust document is the road map as to how the deal with the issues that arise from running the trust. If the document is silent as to a point (Trust Situs) the state’s governing laws take effect.
So if a trust does not specifically make mention of a charitable donation and the trustee makes a discretionary contribution, it is not tax deductible.
So be vigilant when creating your trust documents to ensure that you have spelled out exactly how for funds are to be distributed. Casually telling the Trustee that you want something done after the document if finalized may jeopardize your wished later.