You don't have to be a police officer, attorney or judge to be involved with a criminal case. Perhaps a loved one was charged with a crime, or a neighbor who was arrested for a sex crime could beat the system on a technicality. An extra pair of eyes and ears can change a case. Freedom of information laws entitle you to many of the same records as those who are paid to investigate a case.
Take it from the top; follow through.
Determine which police agency responded to the complaint and obtain a copy of the police report. The incident report or police blotter entry is public record, but chances are you won't be able to see the statements until the suspects have been arraigned, which is usually within a day of the arrest. Request the records of any additional police departments or agencies that were on the scene, even if these are just daily activity logs noting when they arrived and left.
Obtain copies of the statements that victims, witnesses and suspects gave to police. These will be available after the suspect is arraigned. In a felony case, it is important to get copies of these documents shortly after the arraignment, as they may not be available for a while when they are moved to the county court for grand jury proceedings, which determine if the felony charges will stick. The file may be sealed or expunged if the grand jury does not indict the suspect.
Check the case file periodically for supplemental statements or reports, and call the county court clerk's office weekly to monitor the docket. Adjournments are typical in criminal court cases, so don't plan to arrive for a proceeding unless you check the day of or the day before to make sure it will go on as scheduled. If defense lawyers or prosecutors ask for an adjournment, get a copy of those documents as well.
Return periodically to the police agency that made the arrest to check for new information. Document anything in the blotter or daily log that refers to the person who was arrested or to people associated with the case.
Exploit freedom of information laws in the unlikely event that you encounter resistance. Police agencies can require you to file a written request to obtain information, and they reserve the right to take several days to review the request before acting on it. Agencies may require you to specifically identify the document you seek, and you may be denied access if releasing the information will hinder an investigation (Reference 1).