In Witness Competency, Bonnie Sudderth, Judge of the 352nd District Court of Tarrant County, TX, writes:
Long before Robinson and Daubert subjected expert witnesses to a judicial pre-screening process, Texas judges were acting as gate-keepers as to fact witnesses on the basis of competency. In fact, legal history in Texas is replete with many grounds to exclude witnesses due to incompetency, most of which have long-since been abandoned or repealed, such as religion, race and criminal convictions. Two exclusionary grounds remain, however, in the current rules of evidence – witnesses who are mentally incompetent and children.
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