(a) may make such investigations within or outside of this state as it deems necessary to determine whether any person has violated any provision of this article or any rule or regulation hereunder, or to aid in the enforcement of this article or in the prescribing of rules and forms hereunder, and

(b) may require or permit any person to file a statement in writing, under oath or otherwise as the attorney general determines, as to all the facts and circumstances concerning the matter to be investigated. 2. The costs of all out of state travel and lodging expenses relating to investigations by the department of persons who appear to the department to have violated any provision of this article shall be borne by such persons upon a judicial determination that said persons have committed unlawful and fraudulent acts or practices, as defined in this article, or so much thereof as is deemed proper by the court. 3. The department is empowered to subpoena witnesses, compel their attendance, examine them under oath before it or a court of record or a judge or justice thereof, and require the production of any books or papers which it deems relevant or material to the inquiry. Such power of subpoena and examination shall not abate or terminate by reason of any action or proceeding brought by the department under this article. 4. (a) No person is excused from attending and testifying or from producing a document or record, in obedience to the subpoena of the department or in a proceeding instituted by the department, on the ground that the testimony or evidence, documentary or otherwise, required of him may tend to incriminate him or subject him to penalty or forfeiture; but a person may not be prosecuted or subjected to a penalty of forfeiture for or on account of any transaction, matter, or thing concerning which he is compelled, after validly claiming his privilege against self-incrimination, to testify or produce evidence, documentary or otherwise, except that the person testifying is not exempt from prosecution and punishment for perjury or contempt committed in testifying. The department shall compel such testimony or the production of such evidence only after notifying and consulting with any appropriate local prosecuting authorities.

(b) No person shall be excused from attending such inquiry pursuant to the mandate of a subpoena, or from producing a paper or book, or from being examined or required to answer a question, on the ground of failure of tender or payment of a witness fee and/or mileage, unless at the time of such appearance or production, as the case may be, such witness makes demand for such payment as a condition precedent to the offering of testimony or production required by the subpoena and unless such payment is not thereupon made. The provision for payment of witness fees and/or mileage shall not apply to any officer, director, salesman or other person in the employ of any person whose conduct or practice is being investigated. 5. If a person subpoenaed to attend such inquiry fails to obey the command of a subpoena without reasonable cause, or if a person in attendance upon such inquiry shall without reasonable cause refuse to be sworn or to be examined or to answer a question or to produce and permit reasonable examination of a book or paper when ordered so to do by the officer conducting such inquiry, or if a person fails to perform any act required hereunder to be performed, he shall be guilty of a class A misdemeanor punishable as provided in section six hundred ninety of this article. 6. It shall be the duty of all public officers, their deputies, assistants, subordinates, clerks or employees and all other persons to render and furnish to the department or other designated officer when requested all information and assistance in their possession or within their power with respect to all matters being investigated by the department under this article. Any officer participating in such inquiry and any person examined as a witness upon such inquiry who shall disclose to any person other than his attorney or the department the name of any witness examined or any other information obtained upon such inquiry except as directed by the department shall be guilty of a class A misdemeanor punishable as provided in section six hundred ninety of this article.