A person given authority to act on behalf of another person. The person granting the authority is called the principal. A principal can appoint any adult to be their attorney-in-fact and that person does not have to be a lawyer.

Typically, people appoint an attorney‐in‐fact in a written power of attorney, granting the attorney‐in‐fact the power to transact whatever business the principal decides to grant, for example, pay bills , enter into contracts, or make transfers of property. The authority of the attorney‐in‐fact expires when revoked or at the principal's death. 

Under New York Law an "'Agent” means a person granted authority to act as attorney-in-fact for the principal under a power of attorney, and includes the original agent and any co-agent or successor agent. Unless the context indicates otherwise, an “agent” designated in a power of attorney shall mean “attorney-in-fact” for the purposes of this title. An agent acting under a power of attorney has a fiduciary relationship with the principal." General Obligations Law §5-1501(2)(a).

An attorney-in-fact is in a fiduciary for the Principal and therefore must:
  • Act according to the principal's directions or in the principal's best interest.
  • Avoid conflicts of interest.
  • Keep the principal's property separate from the agent's property and property under the agent's control.
  • Keep records of receipts, expenditures, and other transactions.
  • Avoid making gifts to themselves unless the principal has authorized such gifts in the New York Statutory Gifts Rider to the Power of attorney.