It is wholly irrational that the rules governing what may be used to determine settlor intent differs depending on whether the instrument is testamentary or inter vivos. The U.T.C. (as well as the dormant Maryland Trust Code) equalizes the treatment. There is a much greater ability to go beyond (behind?) the document in the case of an inter vivos trust in Maryland than is the case with a testamentary trust. This is not the case in D.C. or Virginia.
Likewise, differences in the dead man’s statutes in the three jurisdictions will impact the terms of the trust. The more modern model (such as embodied in the D.C. and Virginia statutes) permit testimony to come in only if corroborated. In Maryland, regardless of the reliability of the testimony it is barred.