Best tip I learned from lawyer: shut the fuck up!

Ex: a murder was committed on south side of town. You dont know. Cop asks where you're going. You say leaving a friends house on some street (on south side). He asks you to get out of car. Handcuffs are placed on you. Reason: you just came from same area crime happened and your vehicle loosely matches eye witness description. They can legally hold u 72 hours as part of investigation. Sure, they find out youre the wrong guy, but now you've missed 3 days work, were unable to call in, got fired, dog was home alone 3 days, maybe family spent money on lawyer, you need to pay the impound fee, etc.

Life just fucked up by accident. Should've kept your mouth shut. At minimum, dont give specifics.