Measurement of second-order nonlinear optical response of molecules by hyper-Rayleigh scattering (HRS) is often affected by the presence of two-photon excited fluorescence. For crystal violet we found experimentally that both HRS and two-photon absorption induced fluorescence give the same depolarization ratio for the signal. This shows that the depolarization measurement is generally not useful for distinguishing HRS from an unwanted fluorescence contribution. A theoretical explanation of the equality of the depolarization ratio for the two processes is given. Spectral study shows that signals from HRS, and two-photon excited fluorescence for crystal violet are well separated to allow the measurement of beta by standard HRS technique. A modified external reference method is developed to deal with the measurement of beta by HRS for molecules that absorb the second harmonic light. The resulting beta value for crystal violet is 1140 x 10(-30) esu, which is considerably smaller than the Literature value but still amounts to a factor of 33 compared to-that of p-nitroaniline.