To minimize confusion and to make trials manageable, all evidence must be relevant, material and competent. Describe, in your own words, what these three words mean in relation to testimony in a criminal trial?
In legal terms, I would say that “relevant” and “material” mean essentially the same thing. However, “competent” means something different, which means that evidence can be relevant and material without being competent. However, it is hard for evidence to be relevant without being material.
Evidence that is relevant is evidence that tends to prove or disprove a fact that matters in a case. The fact that it tends to prove or disprove must be one that can be legitimately raised in a given case. For example, let us say that a person is being charged with robbery. The prosecutors want to bring up the fact that the person was convicted of drunk driving in the past. This would, in my mind, be irrelevant because the fact that they drove drunk does not tend to prove or disprove the idea that they would rob someone.
Evidence that is material is very much the same as evidence that is relevant. In order for evidence to be material, it has to be evidence that a reasonable person would think is connected to the issues in the case at hand. Therefore, the drunk driving arrest would be immaterial because it does not tend to prove that the person would be likely to rob someone.
However, evidence can be material and relevant without being competent. In order for evidence to be competent, it needs to be admissible. In the context of our hypothetical robbery trial, it would be relevant and material for someone to testify that the defendant is psychologically prone to commit crimes. However, unless that witness is in some way a certifiable expert in the field of the psychology of criminals, the evidence would not be competent because it would just be someone’s idle speculation.
Thus, I would say that “relevant” and “material” both have to do with whether the evidence has any bearing on a case while “competent” means that the evidence can legally be admitted in a trial.
Dealing solely with the issue of testimony in a criminal trial here are the differences between the three. Materiality is a broad factual determination, relevance is a legal determination. Competence is also a legal determination. So let's sift through these. Evidence in the form of testimony can be material. In the Scopes monkey trial, Clarence Darrow attempted to bring in scientific evidence to prove the validity of the scientific method. The evidence was material to Darrow's defense of Scopes. The judge however ruled it irrelevant. The issue was whether Scopes violated the law not whether he was scientifically justified in doing so. Materiality will also involve the intangible aspects of witness testimony, e.g., credibility, demeanor, appearance, voice, emotion. All these indicators for a juror help establish the weight given to a particular witnesses testimony. What if an attorney wants to submit a witnesses recorded statement rather than in person. The recording may be relevant, it is certainly material but if questions about the recordings authenticity or clarity are raised it may not be competent. A witness that has undergone hypnosis or is mentally ill may not be competent even though what they have to say may be both relevant and material. Materiality can be viewed much more broadly than relevance. Testimony about prior bad acts of a defendant may be material evidence but it can be problematic before a jury so most of the time prior bad acts are deemed irrelevant. Can something be relevant and yet not material? Yes, for example, a witness's appearance may be material but his testimony may not be competent.