Conn. Agencies Regs. § 4a-12-11
The Department shall conduct an investigation of a legally liable relative to determine his or her ability to pay. This investigation may include but is not limited to contact with the legally liable relative for a copy of his or her complete Federal income tax return and such other information as determined by the Department as necessary to the investigation. In cases where the federal income tax return is not made available to the Department, such as when no return has been filed or when the legally liable relative refuses to grant permission to the Department to review his or her return, the Department may calculate the equivalent amount of federal taxable income from such other sources as may become available, such as but not limited to information concerning wages, salaries, commissions, etc., provided by employers.
Conn. Agencies Regs. § 4a-12-11