Except in case of emergency detention, whenever any appropriate person shall give to the court information in his or her possession that a child is within the provisions of this chapter, it shall be the duty of the court to make a preliminary investigation to determine whether the interests of the public or of the child require that further action be taken, and to report its findings together with a statement of the facts to the judge. The inquiry may include a preliminary investigation of the home and environmental situation of the child, his or her previous history, and the circumstances which were the subject of the information. To avoid duplication of effort and to take full advantage of all existing facilities, the report of any public agency, or of any private social agency licensed by the department of children, youth, and families, may be accepted by the court as sufficient evidence for the filing of a petition.