THE CRIMINAL INVESTIGATION PROCESS
When a criminal action begins as a result of activity by the police, prosecutor, or grand jury, the criminal investigation process also begins. This involves discovering who committed a crime or, if someone is arrested for the crime, searching for evidence that helps convict or exonerate that suspect. Criminal investigation is a continuous process. It begins when the crime is first discovered and may continue up to the time of a preliminary hearing, a grand jury hearing, or a trial and beyond. Forensic scientists become involved in this process in a number of ways:
• Response to the crime scene—It is the policy of many law enforcement agencies to have a forensic scientist, or perhaps several, attend crime scenes whenever there is a homicide suspected or in cases where there may be a high profile or otherwise notorious crime committed. No one knows better than forensic scientists how to recognize, collect, and preserve evidence within their area of responsibility. Because of time constraints and the need to preserve human resources, forensic scientists are usually sent only to the most important or high-profile crime scenes.
• Analysis of evidence—This of course is the primary task that forensic scientists perform. This is an on-going job during a criminal investigation process. Investigators may bring in evidence to the crime laboratory at many points during the investigation and the results of the analyzes can have profound effects upon the course of the investigation and the outcome of the case. Forensic scientists will issue reports on their analyzes which are then evaluated by the prosecutor and criminal investigators.
• Depositions—At one time, depositions were used almost exclusively in the civil justice system but recently more states have begun to use them in criminal cases. A deposition is a proceeding in which testimony is given under oath but not in court or before a judge. A reporter or recorder authorized to administer oaths is present to take down the testimony. The main purpose of the deposition is to preserve testimony for trial, but it may also be used as a discovery tool to gain information about what the opposition knows and what witnesses are prepared to say at trial. A witness giving a deposition is usually questioned in the same manner as at a trial; the proponent asks questions first, followed by cross-examination by the opponent counsel. One major difference is that there is no one present to rule on objections to questions. In such cases, the objection is lodged and the witness will usually answer the question, but the challenged testimony may not be used at trial until the court has ruled on the objection.
• Court testimony—Along with the analysis of evidence, court testimony is the heart of the job of a forensic scientist. It is the most effective way to impart highly technical and complicated facts and opinions to the judge or jury. Foren sic scientists may also testify at preliminary hearings. They do not ordinarily offer testimony in a grand jury proceeding. Forensic scientists are designated as expert witnesses when testifying within the areas of their expertise. This may confer extra privileges as a witness but may also carry extra duties and burdens. This will be discussed later in the chapter.
