Dealing with a personal injury in Suffolk County? If the agent breaches his or her duties, the principal can sue the agent for either breach of contract or in tort.A principal can be liable for its own actions when it is negligent in hiring, selecting, training, retaining, supervising, or otherwise controlling the agent. An agent may be solely liable to a third party for tortious conduct in certain circumstances. AS Law for AQA Unit 2B The Concept of Liability: Introduction to Tort: Liability in Negligence.