A pretrial motion is a type of motion or request made by attorneys prior to the start of a criminal case. Before a criminal case begins, the defense attorney and the prosecutor will meet with the judge to determine what evidence will be permitted in the trial and what evidence should be withheld.
A defense attorney may request that the judge exclude or withhold any type of evidence that was not obtained lawfully. This will prohibit the use of any evidence that law enforcement agents acquire through illegal searches. Pretrial motions may be used to discredit key witnesses.
For instance, an attorney may provide proof that indicates that his/her opponent's key witness is not competent to provide testimony, and therefore, the witness should not be permitted to testify. The defense attorney may argue that his/her client's confession was not lawfully obtained, and therefore, cannot be used. The evidence included within a case is vital to the outcome of that case. Therefore, pretrial motions are extremely important.