Conn. Gen. Stat. § 12-119a

(b) Any municipality may, by ordinance, provide that the additional amount added to any assessment pursuant to section 12-42 , 12-43 , 12-53 , 12-111 or 12-115 shall equal ten per cent of a taxpayer's assessment rather than the twenty-five per cent additional amount as required by said sections. Such ordinance shall specify that a ten per cent addition to any assessment shall be allowed only if (1) a taxpayer filed a personal property declaration within the time period designated in section 12-41 , and (2) the declaration as filed included complete and accurate information as to the total number and types of items of property subject to taxation in the taxpayer's name. A taxpayer shall be required to establish to the satisfaction of the assessor, board of assessors or board of assessment appeals, as the case may be, that the conditions set forth in the ordinance have been met.