1. A method for verifying the purported identity of a target individual utilizing a number of authorization tissue spectral data from verified individuals having known identities, said spectral data having a plurality of measurement wavelengths, comprising the steps of: obtaining target tissue spectral data from said target individual, said target tissue spectral data having a number of measurement wavelengths; and positively verifying said target individual purported identity by comparison of authorization tissue spectral data and target tissue spectral data relative to a preselected threshold.