Conn. Gen. Stat. § 52-524: Defenses.

All defenses to an action of replevin, other than those to the jurisdiction or in abatement, including avowry, alleging the defendant's right to take and hold the goods, and disclaimer, renouncing any interest in the goods, shall be made by answer or demurrer. Those defenses claiming that the taking is for a lawful cause shall be by way of answer alleging the special facts upon which they are based. If the defendant claims a return of the goods or damages, he shall make the claim by way of counterclaim.