The quantum state resolved reaction dynamics of HCN(O O-0 upsilon(3)) with O(D-1) atoms were investigated by analyzing the complete product state distributions of OH(X (2) Pi(Omega), upsilon, J) and CN(X (2) Sigma(+), upsilon, J) using laser induced fluorescence (LIF). The influence of the CH-stretching mode on the reaction dynamics and different branching ratios was inspected by exciting HCN to its first overtone band of the upsilon(3) CH stretch in the 1.5 mu m region. The oxygen atom in the D-1 state was generated in a laser photolysis of ozone at a wavelength of 266 nm. The measured rotational and vibrational distributions of the products were compared with statistical results from phase space theory (PST). Nearly statistical rotational and vibrational distributions are obtained for CN(X (2) Sigma(+)) in upsilon=0-3. The rotational and vibrational distributions of OH(X (2) Pi(Omega)) are colder than statistically expected. Insertion of O into the CN bond with subsequent hydrogen migration seems to be a better characterization of the the reaction mechanism than an insertion of the oxygen atom into the CH bond. Direct abstraction of hydrogen to form OH is improbable to describe the molecular process.