Following your arraignment, your case will most likely be scheduled for a preliminary conference date. Prior to that date an experienced thorough defense attorney will file and serve a 240.20 demand for discovery, In Response The DA most likely will disclose some of the evidence they intend to use against the defendant, including but not limited to, sworn statements from witnesses, drug/alcohol test results, and photo/video evidence.
After receiving the DAs voluntary disclosure of evidence, your attorney may choose to file motions seeking to suppress the introduction of some of this evidence at trial. Evidence can be suppressed for a number of reasons, such as an illegal search or arrest, an improper police lineup, a coerced confession, or a denial of the defendant's right to counsel or right to remain silent.
In many situations, the court will order a hearing to determine if the evidence will be admissible. At this hearing, the police officer or other relevant witness may be called to testify. The defense attorney can also call witnesses. If it is found that evidence was improperly obtained, then court will prohibit the prosecutor from introducing it at trial.