Legal Question in Civil Litigation in Massachusetts

Massachusetts law applies. Massachusetts consumer protection laws and rules also apply (if the photographer is willing to do business in MA then he subjects himself to all its rules and laws).

Depending on your circumstance (you didn't mention why he refuses to release the photos - it could be a payment issue, a breach of the terms of the contract, or some other justified reason), you should consider sending him a demand letter that cites Massachusetts' consumer protections statute (chapter 93A). I suggest consulting with an attorney first or, at minimum, doing significant research before attempting to write the letter yourself. There are certain requirements the statue places upon the demanding party. If you fail to satisfy the requirements it may negate the purpose of the letter.

If the letter satisfies the statue, and the photographer fails to make a reasonable offer settlement, the photographer may be liable to you for up to three times whatever your damages might be (plus attorney's fees).