The state-resolved and isotope-specific detection of nascent ClO generated from the photodissociation of Cl2O parent molecules is performed by observing single-color (2+1) resonance enhanced multiphoton ionization (REMPI) spectra following excitation in the wavelength range from 336 to 344 nm; additionally state-resolved detection of nascent ClO is performed by observing single-color two photon laser-induced fluorescence. The REMPI spectrum is assigned to the ClO(C (2)Sigma(-),v(')=0<--X (2)Pi(Omega),v=0) transition. The population of rotational states up to J=130 is evidence of large rotational excitation induced by a strong dependence of the excited potential energy surface (PES) on the Jacobi angle gamma. Formation of the (2)Pi(3/2) spin-orbit state is preferred: P((2)Pi(1/2)):P((2)Pi(3/2))=0.30+/-0.05 suggesting significant radiationless transfer from the excited PES to closely lying neighboring states. The anisotropy parameter for the transition is determined to be beta=0.35 independent of the ClO quantum state. The principal excited electronic state is assigned to a B-1(2)<--(1)A(1) transition, in agreement with recent ab initio calculations. The measured beta value is smaller than the limiting value of 1.0, suggesting dynamic reasons and simultaneous excitation to more than one PES. A fast and direct fragmentation process is deduced, where the upper limit for the lifetime of the excited dissociative state is calculated to be 300 fs.