Constraint on ¯ , ¯ from B → K

� = tan�3/2(¯� 0.24 ± 0.03), involving a 1� range for �3/2, 20 ◦ < �3/2 < 115 ◦ , is obtained from B 0 ! K ∗ � amplitudes measured recently in Dalitz plot analyses of B 0 ! K + � − � 0 and B 0 (t) ! KS� + � − . This relation is consistent within the large error on �3/2 with other CKM constraints which are unaffected by new b ! s¯ qq operators. Sensitivity of the method to a new physics contribution in theS = �I = 1 amplitude is discussed.