‘In 2005 my husband’s mother gifted him money to purchase a piece of undeveloped property in New York State. She made it clear that the money was a gift and there was no contract written between my husband and
his mother. The property is in mine and my husband’s name, we have paid the taxes on the property as well. Recently she requested the money back. Does she have any legal recourse?’

It’s unclear from your question whether there was anything in writing at all to indicate whether the money was intended as a gift or a loan (a greeting card that accompanied the money, a letter, etc). If there is anything in writing, then a court would likely look at the writing to determine your mother-in-law’s intent and expectation. If there is nothing in writing, and if there are no witnesses to the transaction, then it would be harder for her to bring a legal action, although if the amount is under a certain threshold, she may be able to go to small claims court. Even in that case, however, absent a writing it would come down to her word versus yours.

All that said, this is your mother-in-law, and your husband’s mother, and so if there is any way to work it out, that would be advisable.