Conn. Gen. Stat. § 42a-2A-108: Option to accelerate at will.

(a) A term in a lease agreement providing that one party or the party's successor in interest may accelerate payment or performance or require collateral or additional collateral “at will” or when the party “deems itself insecure”, or words of similar import, shall be construed to mean that the party shall have power to do so only if the party in good faith believes that the prospect of payment or performance is impaired.

(b) In a consumer lease, the burden of establishing good faith under subsection (a) of this section is on the party that exercised the power. In all other leases, the burden of establishing lack of good faith is on the party against which the power has been exercised.