The modern law of evidence has a broad scope and uncertain limits, and it is influenced by two key features of adversarial procedure, autonomy and orality of evidence. The adversarial system in common law jurisdictions usually involves adjudication between two competing version of events advanced by the expert witnesses. Experts sometimes forget that their ultimate duty is to the court and must be independent and objective irrespective of being contracted by a party. The witness qualification to act as an expert is technically a matter of competence to be determined by the court, and it is conceptually linked with the first hurdle in the admissibility of the opinion evidence. Where doubts arise regarding the expert witness qualification, the modern practice is to receive the evidence, although its weight may be open to serious adverse comments if the apparent expertise is not translated to reality.