Call the non-emergency line of your local police department. All police departments maintain a non-emergency phone line. Calling the non-emergency line is appropriate when you wish to report evidence of a crime that has already happened and no longer constitutes an emergency situation. To find the non-emergency phone number for your local police department, check the phone book or the website for the town where the crime took place.
Call your state's anonymous tip line. Calling an anonymous tip line is most appropriate when you wish to report witnessing a serious violent crime and you do not wish to be identified because of concerns about your safety. Most sheriff's departments maintain an anonymous tip line. Additionally, WeTip (see Resources) maintains a nationwide anonymous crime reporting hotline.
Visit your local police department in person. You can visit your local police department during normal business hours to report that a crime has been committed. Unlike the other reporting methods, you can present physical evidence of the crime. Your local police department will ask you to provide a statement detailing facts about the crime you wish to report.
File an online crime report. Some municipalities and sheriff's departments maintain an online system for reporting non-emergency crimes. Similar to a non-emergency phone line, an online crime report system is most appropriate for reporting crimes that have already happened.