Madison and his adult son lived in a house owned by Madison. At the request of the son, Marshall painted the house. Madison did not authorize the work, but he knew that it was being done and raised no objection. However, Madison refused to pay Marshall, arguing that he had not contracted to have the house painted. Marshall asked his attorney if Madison was legally liable to pay him. The attorney told Marshall that, in their state, several appellate court opinions had established that when a homeowner allows work to be done on his home by a person who would ordinarily expect to be paid, a duty to pay exists. The attorney stated that, on the basis of these precedents, it was advisable for Marshall to bring a suit to collect the reasonable value of the work he had done. Explain what the attorney meant by precedent and why the fact that precedent existed was significant.