Plaintiffs inIsaacson v Law Off. of Norman L. Horowitz, LLC    2013 NY Slip Op 32598(U) October 18, 2013;  Supreme Court, New York County;  Docket Number: 112174/2010;  Judge: Joan A. Madden were commercial tennants who became disenchanged with the building after a big burglary.  They had a ‘good guy" guarantee, and attempted to terminate their lease without penalty.  This attempt did not turn out well.  However, Supreme Court held that they could not prove exactly how the landlord would have handled the case, and could not show ascertainable damages.
 

"Upon instruction from defendants, plaintiffs sent the landlord written notice that they were vacating the premises as of July 31, 2009, with a line for the landord to countersign.  The landlord refused to do so, notifying plaintiffs of this fact in a letter to defendants, where the landlord also declined to accept surrender of the lease, and instructed defendants that the landlord would hold plaintiffs to their rent obligations.

Defendants apparently did not inform plaintiffs of this letter and continued to advise plaintiffs to move forward with vacating the premesis.

Plaintiffs retained their present counsel after the decision was rendered. On June 25, 2010, the court entered an order and judgment awarding the landlord $851,618.27 against the tenants,
representing unpaid rent, interest and penalties. An award of $595,235.92 was rendered against the guarantors, under the guaranty. However, plaintiffs’ new counsel eventually negotiated
a settlement of the entire matter for $500,000. In the present action, commenced on September 15, 2010,plaintiffs seek damages against defendants on the ground that, but for defendants’ faulty advice, plaintiffs could have settled with the landlord before vacating the premises, and before the
commencement of any lawsuits, at a much lower figure than the $500,000 settlement amount which was eventually reached. In the present motion, defendants move to dismiss the
complaint, on the ground that plaintiffs cannot prove that they would have fared better in settling the amount had they not heeded defendants’ advice."

"If proximate cause is not established, the action must be dismissed "regardless of whether it is demonstrated that the attorney was negligent." Schwartz v Olshan Grundman Frome & Rosenzweig, 302 AD2d at 198. Moreover, the damages claimed for legal malpractice must be "actual and ascertainable" resulting from the proximate cause of the attorney’s negligence. Ressis v. Wojick, 105 A.D.2d 565, 567 (3d Dept 1984), lv. denied 64 N.Y.2d 609 (1985)

Plaintiffs cannot prove that "but for" defendants’ advice they would have settled for less than $500,000. Specifically, there is no proof available that would show that the landlord would have discounted the rent in any amount, less a  specific amount, such as 41%. Moreover, contrary to plaintiffs’ position any testimony by the landlord’s representative would be insufficient to establish actual and ascertainable damages as he would be speculating as to what the landlord might  have done years earlier."