The Scale Method was applied for analysis of experimental and theoretical prompt fission neutron spectra (PFNSs). This approach allowed us to demonstrate evidence from several experiments that had not been discussed before. The comparison of experimental and calculated data; the analysis of experimental PFNSs from neutron-induced fission reactions for 232Th, 233U, 235U, 238U, 237Np, and 239Pu; and the analysis of spontaneous fission for 242Pu, 246Cm, 248Cm, and 252Cf gave new results that may change our understanding of the neutron emission mechanism.