Collection and storage of speech has become a very common phenomenon in recent times, thanks to the availability of the necessary electronic devices such as microphones and memory. All personal computers, cell phones and the like come equipped with these devices. With literally billions of people over the world having mobile phones, audio records are rapidly getting built up, sometimes without the knowledge of the user. In fact, many business and financial transactions are carried out over the phone without any authenticating documentation, thus creating a host of new legal problems. However, if this new mode of business is in the future likely to replace (with some degree of regularity) the conventional signed paperwork, we will need a robust authentication method for voice. Yet, even with the increased use of voice technology, it seems highly unlikely at the moment that courts of law will accept the current speaker recognition technology as forensic evidence on par with signed documents, fingerprints, or DNA. The reason is that compared to a fingerprint or DNA or even a handwritten signature, voice has far greater variability. In addition, fatigue, common cold, emotions, among other factors can change the voice sample sometimes beyond recognition. In fact, in everyday life we as humans can sometimes incorrectly identify a speaker, so imagine how difficult it for a machine to consistently identify a speaker accurately. In spite of such limitations, which undoubtedly mitigate the evidentiary weight of speaker identification and verification findings that are presented to the court, speaker recognition can still play a significant role as a prime investigative tool in criminal prosecutions.