Breach of fiduciary duty is a cause of action or claim in civil litigation (lawsuits) that provides the legal basis for a person or entity to recover its damages/losses when there is a special relationship based on trust and confidence (attorney and client or trustee and beneficiaries) and the party who owes the fiduciary duty breaches its duty of loyalty (conflict of interest) or duty of care (informed judgment in decision-making).

In Louisiana, a breach of fiduciary duty occurs when an individual or entity, who is obligated to act in the best interest of another due to a special relationship of trust and confidence, fails to do so. This can involve an attorney not acting in the best interest of their client, or a trustee not properly managing the assets for the beneficiaries. The fiduciary duties include the duty of loyalty, which requires the fiduciary to act without any conflict of interest, and the duty of care, which requires the fiduciary to make informed and prudent decisions. When these duties are breached, the affected party may file a civil lawsuit to recover damages. Louisiana law, influenced by both civil and common law traditions, will consider the specifics of the fiduciary relationship and the nature of the breach when determining liability and damages. The Louisiana Civil Code and case law provide the framework for these types of claims, and the remedies can include monetary compensation, restitution, and in some cases, punitive damages.