Can a police officer stop and search me on the street for no reason?
Police have authority to stop you on the street for no reason, but they cannot search you without reason. The Supreme Court has held that law enforcement officers can approach and talk to anyone.
Most states have laws that require every citizen to carry identification and requesting proper identification has also been upheld. If you refuse to identify yourself, you could be arrested in some states. But if an officer approaches you, requesting identification is as much as they can require of you. Everything that happens after you give the officers your name depends on whether you want the conversation to continue. Officers will try to make casual conversation with you like, “What do you have in the bag?”. How you answer and what you volunteer is up to you. You are within your rights to simply end the conversation by telling them that anything in the bag is your personal property, and walk away.
Withholding Consent to Search
If the police ask you “do you mind if we conduct a search of your person,” you are also free to refuse their request. Just because the police come near you, they do not automatically have authority to search you. In order to justify a pat down of the outer part of your clothes, officers must explain why they had a concern for their safety. If officers do search you, they will usually follow up by asking permission to reach in your pocket. They are asking you for permission because they know that without your consent, they can’t reach in. Once you say “okay”, they can search. Firmly, but politely, tell them "no".
What to Do When Faced with an Illegal Search
Witnesses and evidence will help your situation. Call out to other witnesses to notice you and the police if you are being harassed. Most officers are less likely to engage in illegal searches when they know they are being watched. If you see the police approaching you long enough in advance, you might dial your home number on your cell phone and put it on speaker phone. Whatever is said can be recorded on your home voice mail for use later. If criminal charges are filed against you, you can then file a motion to suppress and present evidence that you did not consent to the encounter with the police and any subsequent searches were illegal. With the evidence against you suppressed, the charges will be dismissed. In addition to a motion to suppress, you may have additional civil remedies for violations of your civil rights. These types of suits tend to be more difficult. Before you decide the best direction to go, consult with an attorney in your state to see what additional remedies are available in your jurisdiction.