In the United States, a child witness is a person who is under 18 years of age at the time of testifying. The law does not clearly define the minimum age to be a credible witness. This assessment is made by the court and law enforcement authorities, with the help of an expert in psychology or child psychiatry. However, it is extremely important in this context to protect the child’s psyche and, at the same time, to use methods that will allow the interview to be conducted and reliable evidence to be obtained in the case. As Dr. Grzegorz Skrobotowicz emphasizes, it should be remembered that a child who has been a victim of a crime has already had traumatic experiences, which is why it is important for law enforcement authorities to use good practices of qualified teams and entities that support and protect children in this area. Such entities include the „National Children’s Advocacy Center”, and this expert opinion indicates good practices in this area that this and other entities promote.