Legal Question in Criminal Law in Michigan

Re: Failure to Report a Witness Crime

No. There is no legal duty for an eye witness / bystander to 'report' a crime to police. However, many people would consider it a moral or ethical duty ... but you don't get prosecuted in this life for those things.

An accessory is someone who knowlingly aids/assists another person who IS committing the crime ... and the person is intending on giving that person aid for that crime, including help covering the bad's guy's tracks or otherwise helping him avoid detection, prosecution, punishment, etc. (If a bank robber jumped in a cab to get away and the cabbie did not know that his passenger was a fleeing robber, then the cabbie is NOT an accessory because he's not intentionally helping the person commit or avoid detection for a crime.)

An "aider/abettor" is someone who helps another person commit a crime (e.g., a 'look-out', a get-away car driver). That person can be charged as if he committed the crime that the principal defendant was committing (e.g., the look-out is charged with the actual bank robbery even though he may have never entered the bank).

An accessory-after-the-fact is someone who helps AFTER the crime is completed (the defendant has retreated to a place of safety). The accessory generally helps cover up the crime or helps the defendant avoid detection. "Accessory after the fact to a felony" is a specific crime in and of itself. Its penalty is up to 5 years and/or $10,000 fine. See MCL 750.505.