A leading question is a question asked of an individual during an examination that is deliberately worded in a way to infer the desired answer.
"Leading the witness" is the act of asking a witness questions that are phrased in such a way that it suggests a specific answer or essentially puts words into the mouth of the witness.
The purpose of allowing witnesses to testify in court is to give them the opportunity to explain to the judge and the jury what they perceived – their unbiased and uninfluenced opinion. This cannot happen if a lawyer is leading a witness to answer in a specific way. Therefore, leading questions are generally not allowed within the United States legal system. However, there are common exceptions to this rule:
If an attorney believes that another attorney is leading their own witness, then they can object. It will then be decided by the judge whether or not the question and answer will be allowed.
Leading the witness is fairly easy to recognize once you know the standard:
"What color was Mr. Smith's jacket?" or "What color was the jacket that you saw that night on the person leaving the scene?"
It would be seen as leading the witness if the attorney asked the question in this manner: "Mr. Smith's jacket was red, wasn't it?"
(This question is leading because it suggests an answer by providing an exact location for the testifier. The non-leading way to ask this question would be: "Where were you on the night of November 13, 2013?")