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1991 Donald Trump Masqueraded as Publicist-The Voice Is NOT Donald Trump

Friday, May 13th, 2016

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If you are just tuning in, the lead story from Washington Post this morning is regarding a recording that was thought to be Donald Trump. Trump denied the recording was his voice. Primeau Forensics was asked by the media to perform a forensic voice identification test to determine if the unknown voice in the Washington Post story features the voice of Donald Trump.
Primeau Forensics located a C-Span interview from 1991 titled ‘Donald Trump on Economic Recovery’. We chose this recording as the ‘known’ Donald Trump voice for forensic comparison. We chose this older voice sample because it was closer in time to the ‘unknown’ recording.
The biometric software program that we used is a Speech Pro Product titled ‘SIS 2’. We formatted each speech sample based on training received from Owen Forensic Services and loaded them into the biometric software. The result was a 98% mismatch meaning the ‘unknown’ voice recording that surfaced in the Washington Post today is NOT the voice of Donald Trump.
The image below is a screen shot of ‘SIS 2’ with the test results highlighted.

 

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Three Tips to Successful Voice Identification and Speaker Recognition

Thursday, April 21st, 2016

yamaha-mixer-1474888As an audio forensic expert, one of my day-to-day activities is voice identification and speaker recognition. Primeau Forensics receives calls on a weekly basis from concerned businesses and citizens for help identifying a derogatory voicemail message or threat to an employee or supervisor.

Also common are requests to enhance and clarify fraudulent calls placed to insurance or credit card companies during which a bogus transaction takes place by people impersonating account holders.

In cases that I have testified on successfully this year, voice identification has assisted the courts in settling disputes from individuals who have falsified their voice identification.

So how do you know if you have a recording that could successfully be identified? Here are three things to consider before proceeding with the voice identification test.

1. Does the recording have at least 20 words?

In order to perform a successful voice identification analysis, there must be enough of the ‘unknown’ voice to analyze. If a recording has between 20 and 50 words, it is an ideal sample of the unknown voice. More than 50 words can be excessive for an accurate test, though extra voice samples can’t hurt.

2. Can an exemplar of the suspected person be created?

In order to complete a voice identification, a sample of the suspected person or ‘known’ voice must be created under the supervision of the forensic expert. This sample, or exemplar, of the known voice should be recorded in the same manner that the unknown voice was recorded in and the suspected person should read the exact same words spoken in the unknown voice sample. Without this exemplar recording, a voice identification test may not be possible.

3. How has the court your litigation is being handled in voice identification in the past?

There have been both positive and negative rulings on voice identification over the years. As technology grows, voice identification has become much more accurate and is becoming more and more accepted. The oral spectral method is now being accompanied by speech biometrics as a means of confirming results. When both of these methods are used, there is a strong amount of scientific evidence that is produced. With objective scientific evidence, the court is much more likely to accept these analyses into evidence.

Part of the reason oral spectral voice identification has been under criticism in the past is because much of the testing procedure is subjective to the voice identification examiner. Electronic measurement and critical listening are the two primary testing procedures.

Using voice biometrics in addition to the oral spectral method adds to the credibility of the voice identification test because the software has several algorithms that measure the known and unknown voices scientifically to arrive at a percentage of certainty that the known and unknown voices are either identical, might be the same or are not the same.

The five levels of voice identification results are:

  • possible identification
  • probable identification
  • possible elimination
  • probable elimination
  • inconclusive

Based on the increasing technology and increasing need for voice analysis, it is our opinion that voice identification is here to stay. Scientific methods for voice identification are constantly being tested and improved by researchers and software development companies. It is a powerful tool that more and more litigations are making use of.

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Voice Identification: Characteristics of an Unknown Voice

Monday, January 12th, 2015

voice identificationOne of the most important elements of Voice Identification is the ability to recognize the characteristics of the human voice. There are many elements to distinguish these characteristics, some audial, some visual.

Think about when you have your back to a person who enters the room and says hello. If it is your child, spouse or co-worker, I bet you recognize them immediately because you are familiar with their voice. This is the starting point for voice identification; becoming familiar with the characteristics of the unknown voice.

I began editing spoken word on reel-to-reel tape with razor blades and splicing tape. I had to learn to visualize the words in my mind’s eye in order to cut the tape in the right place. Today, we have software programs that display the waveform and sound spectrum of the spoken words, which make the editing process more accommodating. The editor can see the
way the words look on the computer screen while deciding where to make the edit and connect the sentences, removing the stutters, coughs, gaps and mistakes.

During the editing process, you will learn to listen for voice characteristics almost subconsciously. These characteristics include the way the words are spoken, the word pronunciations, vowel and consonant pronunciations, the recording noise floor (unwanted background noise), the way the words flow together, and significant patterns of speech you may detect, like accent, dialect and impediments, nasal cavity resonance, voice tone and inflection and speech pacing.

Pay attention to both differences and similarities from recording to recording, and take notes on your observations building a speech database for when writing the report.

Exemplars are defined as expert supervised audio recordings of predetermined spoken word samples for the purpose of voice identification comparison. During the exemplar creation process it is important to coach the person (subject) speaking for the recording into the same level of energy as the evidence recording of the unknown voice. Listen to the energy and attitude of the voice you are examining (evidence or unknown recording). Do you hear a mood or psychological characteristic in the voice?

In some bomb threat recordings I have examined, the speakers have an angry, sad or depressed attitude in their voice while speaking the recorded words. It is important to note that at the time of creating an exemplar, the subject is often not in the same psychological state as the individual in the unknown recording. While making the exemplar, do your best to coach the person (suspect) to speak with the same energy as the voice on the evidence recording.

Your critical listening ear will help you complete this process to the best of your (and their) ability. You have to listen critically beyond the subject’s current mood, because it is often difficult to coach them into the mood of the person on the evidence recording. Listen for specific speech characteristics in the exemplar and evidence recordings. What do you notice about the unknown voice that is characteristic of the known voice?

To practice, spend some time listening to spoken word recordings. These can be in the form of talk radio, podcasts and audio books. Write down speaking characteristics of the voice recordings like this:

• English accent


• Southern accent


• Consistent sibilant “s”


• Consistent long “a”


• Medium pitch, low pitch, high pitch

• Emphasis on “al” as in “halp” instead of “help”

• Does the subject have a characteristic rhythm to his speech or a pattern of delivering words and pausing?

Listen to several spoken word recordings and make a list of speech characteristics. Take notes on your observations.

Only through practice and experience will you become familiar with voice identification. When creating a new audio comp or assembly file in Sony Sound Forge or Adobe Audition, you will be able to listen to the speech sections that you are comparing repeatedly and with easy access. Back-to-back critical listening is an extremely important tool for voice identification. It is the best way to develop your critical listening skills and begin to recognize the different speaking characteristics of each voice examined. The familiar and unfamiliar speaking samples can be identified and characteristics can be easily noted.

Learn more about Voice Identification and Critical Listening in Forensic Expert Ed Primeau’s new book, That’s Not My Voice! available now on Amazon.

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Mayor Rob Ford Toronto Voice Identification

Wednesday, December 11th, 2013

Back at the end of October, I was contacted by Nicole Bogart from the Global News in Toronto who asked that I conduct a voice identification between known samples of Mayor Rob Ford and a male caller to a radio show named Ian. They believed that the caller who was defending the mayor was not a person named Ian but rather Rob Ford himself.

In the video below, I explain my process and play samples of the audio’s that were used to compare and arrive at my conclusion.

To read the full Globe story, click HEREhttp://globalnews.ca/news/950387/forensic-audio-experts-mixed-on-whether-ian-from-etobicoke-caller-was-rob-ford/

 

For more on Voice Identification, check out Ed Primeau’s latest book, “That’s Not My Voice!” available on Amazon.
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Voice Identification and Critical Listening

Wednesday, September 18th, 2013

critical listening Imagine for a moment that you’re sitting at home after a long day at work, enjoying some time in your living room, watching TV or the like.  All of a sudden, you hear the door open behind you.  You sit and wonder who could have walked in, until the anonymous person speaks.  The second you hear their voice, you recognize and register immediately who has entered the room. The same scenario can happen all day at work as well. You learn to recognize your co-workers voices after hearing them all day for several months, even years.

As these examples show, we recognize and interpret characteristics of voices very quickly. Why is this? Vocal characteristics are very distinct amongst all people regardless of race, gender, or ethnic background. If you spend a decent amount of time around someone, you become used to the vocal characteristics they express and can immediately correlate those characteristics with the identity of who is speaking to you.

Vocal Identification in audio forensics relies on the ability to recognize these characteristics in any unknown human voice. In the examples above, the repetition of exposure to those vocal characteristics make you respond without even thinking twice about who could be behind you.  The difference in regards to audio forensics is that a forensic expert doesn’t always know anything about the voice in question. This requires the forensic expert to rely on their ‘critical listening skills.’

So, how is this done? What specific characteristics are forensic experts actually looking for?  They look for the types of speaking characteristics that could be relevant and specific in identifying a person’s voice.  Everyone has very distinct features to their voices, regardless of how slight or severe they might be.  When compiling information for voice identification, the forensic expert must listen over and over to the unknown voice with pen and paper taking scrupulous notes of all speech characteristics. They focus specifically on things such as inflection, pronunciation of certain words, any form of an accent, stutters and lisps, amongst other variables. Make careful and precise notes about all of these variables.  They try to be as SPECIFIC as possible.  The forensic expert will then create a voice profile for this person.

If by chance the forensic expert has access to the suspect thought to be the unknown voice, this puts them at more of an advantage.  The goal then is to create an exemplar of that person saying the same message in question with the same delivery heard in the recording. This is called an ‘exact exemplar.’ They will review and compare notes from both the original recording and the exemplar itself. An exemplar gives you a more neutral quality, and isn’t biased by background noise, feedback, or any other external features that may have affected the original recording.

By understanding the critical listening phase of voice identification, you will better understand the value and importance of voice identification as a tool for the audio forensic examiner and audio forensic expert.

For more on Voice Identification, check out Ed Primeau’s latest book, “That’s Not My Voice!” available on Amazon.

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Crisis Management and Voice Identification

Tuesday, April 16th, 2013

Voice IdentificationHistorically, voice identification has had its ups and downs in the United States Courts. Forensic experts that practice voice identification follow voice identification processes that have been established in the scientific community. However, there are times the voice identification process is necessary with less than perfect circumstances.

In my opinion, especially under less than perfect circumstances, the voice identification process is not always black and white. Litigators need help building a case to either prosecute or defend and some of the main evidence is voice recordings. A majority of the time these voice recordings are threatening and disturbing to the recipients who are targets to the threats left in these messages. Some messages are longer than others – it is the short messages that pose the biggest challenge for voice identification experts.

According to the scientific community, in order to conduct voice identification, the following process is followed by the audio forensic expert:

  • Make sure the unknown recording has sufficient amount of words
  • Make sure recording is clear and free from noise
  • Sufficient frequency range of recording (telephone calls are leader in lack of frequency)
  • Exact exemplar creation using available exact electronics 
  • Multiple exemplar recording samples of suspect’s voice
  • Test aural (listening-single and multiple word formation) and spectrographic (visual-electronic measurement)
  • List all similarities and differences for both aural and visual testing
  • Create comparison back to back sample file using evidence and exemplar samples

There are five standard conclusions:

    1. Positive identification
    2. Probable identification
    3. Probable elimination
    4. Positive elimination
    5. Inconclusive

 

In order to arrive at a positive conclusion, the audio forensic expert must find a minimum of 20 speech sounds and/or electronic/spectrographic identifying or disqualifying characteristics. However in the case of a crisis, investigators ask voice identification experts to determine as exact as possible what percentage of certainty can be established with regard to what I consider nontraditional voice identification.  In this case I follow as much of the established protocol as possible and provide a percentage of certainty in my findings.

Threatening calls in the workplace require the identity of the caller be revealed or at least narrow down the list of suspects so management can take appropriate actions to protect other employees. These threatening calls are most always short, which presents challenges to the forensic expert due to the number of words available to be compared to known speech samples. In this case the voice identification examiner needs as much exemplar (known speech) recording as possible to use for comparison purposes.

I consider these threatening phone calls and messages to fall under emergency ‘crisis’ situations and adjust the voice identification procedure to accommodate the client and attempt to identify two or three suspects.

Another tool that helps the audio forensic expert in these crisis situations is the voice identification line up. In this style of voice identification testing, it is necessary for the voice identification expert to create a comparison file with back to back samples taken from all suspect exemplar recordings. This comparison digital audio file can be closely examined very quickly noting all similarities and differences to determine a suspect.

Many companies have a database of absenteeism calls from employees. These voice mail recordings are great alternates to exact exemplars because they were recorded through the phone similar to many of the threatening calls. For this reason, I recommend that companies maintain a voice mail recording database for crisis management cases like these. Then when the voice identification expert is called on to provide their opinion about the suspects for investigators to consider, the voice identification expert can help strategize additional steps and strategies to take that will help solve the mystery.

I have found that once a suspect has been identified preliminarily and asked to cooperate in creating an exact exemplar, they either confess or investigators discover additional clues to help with the crisis investigation.

In one particular voice identification case, my preliminary testing helped reveal two suspects. We discovered that the threatening call was made from a company phone. There was a CCTV camera near the company phone which provided video of one of the suspects near the phone the day and time the threatening call was made. The identification could not have been made without the preliminary nontraditional voice identification test that helped identify two suspects. That helped me know who to look for in the CCTV video. The CCTV digital video recording was poor but I was able to identify clothing logos on the person in the video with the suspect who often wore similar clothing. Investigators were able to leverage a confession once the suspect was confronted with this preliminary evidence.

So, although formal voice identification is not always possible, an audio forensic expert can aid in the investigation of threatening voice mail messages and help keep the attacked workplace safe for other employees.  When the case reaches a point when a formal charge is made, the voice identification testing can then be directed to traditional testing protocols.

For more on Voice Identification, check out Ed Primeau’s latest book, “That’s Not My Voice!” available on Amazon.

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Did George Zimmerman Cry for Help? – The Trayvon Martin Murder Trial

Wednesday, July 11th, 2012

trayvonAs you probably have read in previous blog postings, I’ve made some comments about the 911 and other police recordings that were involved in the Trayvon Martin shooting case. My opinions were published in the Orlando Sentinel and I also made some appearances on MSNBC and CNN as well as Fox News.

I was contacted by a producer at The Today Show shortly after they acquired a copy of an exemplar that the police made of George Zimmerman’s voice. They made the exemplar (sample of Mr. Zimmerman’s voice) so that it could be compared to the cry for help in the 911 police recording.

The Today Show wanted me to form an opinion and comment while on camera regarding the exemplar that was made by the police. I decided not to go on camera with a comment because the prosecution in this case named me as an expert witness. I did not feel a media update would be appropriate even though the prosecution has yet to contact me since naming me as an expert witness.

However, I do want to go on record and comment that a more appropriate or exact exemplar needs to be made of George Zimmerman’s voice in order to conduct a proper voice identification test.

I believe the police did the best that they could in order to recreate that sample or exemplar of George Zimmerman’s voice. They had him say the word “help” for comparison to the cry for help on the 911 recording. The word “help” was shouted the night this incident took place. The question is who shouted help?

However, what was not done properly when creating the exemplar was the delivery of the word “help” by Zimmerman. The reason being that, it was very different than the long, drawn out scream of help that is heard in the background of the 911 recording which is posted on several places on the Internet. I first learned about that recording from the Mother Jones Blog and, of course, I have discussed it on previous blog posts as well.

I originally formed an opinion that the cry for help was not George Zimmerman’s voice, which was the opinion I shared when asked by the major media. I formed my opinion by using my own critical listening skills that I’ve acquired after 28 plus years as an audio forensic expert who also performs voice identification. No scientific voice identification testing was done because I did not have the proper resources.

The bottom line here is that this has turned into a media frenzy. People in the United States have already formed an opinion as to whether or not Zimmerman is guilty. In some social circles, this case has even taken on a discriminatory slant due to the fact that people are choosing sides based on their own personal views pertaining to racial discrimination.

It’s very unfortunate that Trayvon Martin was shot and killed by George Zimmerman; this is a fact that we know for sure. But it is up to the court and the due process of the United States to determine whether or not George Zimmerman acted in self defense with regard to the shooting.

The way to properly record a voice identification exemplar or sample of the accused voice is to have the person recreate the distance of the cell phone call exactly like the police did. Additionally, the delivery of the words need to be as similar to the original as possible. In this case, I believe that the police could have turned to the FBI for help recording this exemplar.

As an audio forensic expert who has been named as an expert witness in this case, I would have been happy to help create this exemplar as well. And why it was released to the media before consulting with the expert witness team is unknown to me. Below is a link to the audio file that was recorded by the police of George Zimmerman’s voice which was considered an exemplar. Also, s the original 911 call is now. Listen to both of them and decided whether or not it is the voice of George Zimmerman.

[audio:http://WWW.AUDIOFORENSICEXPERT.COM/wp-content/uploads/2012/07/Female-911-Call-with-Gunshot.mp3|titles=Female 911 Call with Gunshot] [audio:http://WWW.AUDIOFORENSICEXPERT.COM/wp-content/uploads/2012/07/VoiceExemplars_03222012_643pm.mp3|titles=VoiceExemplars_03222012_643pm]

For more on Voice Identification, check out Ed Primeau’s latest book, “That’s Not My Voice!” available on Amazon.

photo credit: Crossing the Line via photopin (license)

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Are Audio Forensic Procedures Reliable in the Legal System?

Wednesday, March 7th, 2012

legal systemHow reliable are audio forensic procedures in the legal system? A student recently asked me that and asked about some of the ins and outs of a career in audio forensics. The student’s specific questions are below and are followed by my answers.

1. How often is speech-based evidence used in court? It’s used very often. Voice identification evidence helps a court to identify people involved in a case and put the puzzle pieces of a case together. Furthermore, voice identification can also sometimes provide substantial enough evidence to cause people to be convicted or released.

Is it a common or rare occurrence? Our business has grown significantly, so I would say that audio forensic procedures in the legal system are common.

2. Is voice identification a lengthy process? It can take up to 4 hours for the average case. This includes 3 types of examination. Audio forensic experts visually examine the sound wave, comparing the evidence and an exemplar (a voice sample of the accused). Next, Audio forensic experts electronically measure the evidence, which is then compared to the exemplar. Finally, and most importantly, audio forensic experts critically listen to compare how the words are spoken and pronounced in the evidence and the exemplar.

3. Are there any factors which can create problems when dealing with a recording? Yes, difference in age between the recording in question and the creation of the exemplar creates problems. People’s voices change with the passing of time. One of the nationally accepted standards for comparing voices is that the voice samples must not be more than six (6) years apart.

4. Is voice identification considered to be reliable within the legal system? YES. However, it’s argued more in some states than others. The forensic expert must carefully examine all scientific evidence and follow procedures. Both law enforcement and defendants seek assistance from audio forensic experts.

For more on Voice Identification, check out Ed Primeau’s latest book, “That’s Not My Voice!” available on Amazon.

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Why is Voice Identification Important?

Wednesday, February 8th, 2012

voice identificationToday, more than any other time in the history of the United States and the world, we find our court systems full of digital audio files in the form of evidence. As an audio forensic expert, I have testified in many cases in the United States and worked on cases in India, Turkey and France. One thing I see time and time again, regardless of geography, is the misunderstanding of how voice identification can aid in litigation.

The American Board of Recorded Evidence here in the United States has established a probability factor with regard to voice identification. This board is a part of the American College of Forensic Examiners International.

When conducting a voice identification test, I look for spectrums that match the recording in question against the exemplar.  An exemplar is a comparison recording that a forensic expert creates of the voice in question for comparison purposes. Does each recording include spectrums that are similar?

Even more important are the words themselves. The way the words are pronounced, the pacing of the words pronounced, the space between the words, the articulation of the words and the consistent delivery style are all considered.

No two human voices are the same just like no two fingerprints are the same. Despite attempted voice disguise cover up, a trained forensic expert can identify a voice and compare it to another voice to determine identification.

With experience, a trained audio forensic expert can use voice identification skills in a variety of ways and help uncover the truth behind audio recordings.

In recent months I have used traditional voice identification techniques to identify a new Elvis Presley song, singer in a motion picture soundtrack as well as confirm the difference between a father’s and son’s voice for a civil litigation.

Some would say this is not a proper way to conduct voice identification testing. However, in my humble opinion, with 28+ years of voice identification experience, I believe as long as the audio forensic examiner has experience, an exemplar that is as exact as possible and the necessary tools (hardware and software), nontraditional voice identification is possible.

Using the new Elvis Presley song discovery, turns out that I was right with my positive identification. Two Elvis Presley historians agree with me that this new song is indeed Elvis Presley. After I completed my voice identification testing his record company came forward and confirmed the session date and time the recording was made.

The bottom line is that going forward, voice identification will continue to be an important part of the litigation process when audio evidence is involved.  The science is as exact as the expert is experienced.  The more experienced the expert, the more solid the expert’s report.

For more on Voice Identification, check out Ed Primeau’s latest book, “That’s Not My Voice!” available on Amazon.

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Voice Identification Standards: Practical and Official

Friday, January 6th, 2012

spectrographAs an audio forensic expert who conducts voice identification, I receive calls from people around the world asking about voice identification. The American Board of Recorded Evidence provides voice identification standards that help me determine if I can identify a piece of audio evidence.

Some of the requests I receive are a stretch because the audio in question does not have enough words spoken in order for me to create an exemplar.  An exemplar is one of the most important tools to a voice identification test.  The exemplar must be made as closely to the original recording as possible.  The audio forensic expert often does not have as much control over the technology when making the exemplar as they would like.  In that case careful attention must be paid to the variable electronic readings in spectrograph measurement allowing or compensating for the variable.

In other words, if a piece of audio evidence was a telephone intercept or voice mail recording, the exemplar must be made using a telephone and recording device as similar as possible to the device that was used to create the original recording in question. This is where the attorney representing our side in the litigation comes in.  The attorney must petition the court during discovery to help the audio expert learn what equipment was used to record the original evidence.

This process was especially important back in the analogue days. Today’s digital recordings create much higher quality recordings and have different authentication processes.

Here are the American Board of Recorded Evidence voice identification requirements as accepted in the scientific community:

Standards for Comparisons Determination

The following are the standards accepted nationally by all professional organizations involved with voice identification, including the FBI, the Audio Engineering Society, the International Association for Identification, and the American Board of Recorded Evidence:

  • IDENTIFICATION: At least 90% of all comparable words must be very similar aurally and spectrally, producing not less than twenty (20) matching words. The voice samples must not be more than six (6) years apart.
  • PROBABLE IDENTIFICATION: At least 80% of the comparable words must be very similar aurally and spectrally, producing not less than fifteen (15) matching words.
  • POSSIBLE IDENTIFICATION: At least 80% of comparable words must be very similar aurally and spectrally, producing not less than ten (10) matching words.
  • INCONCLUSIVE: Falls below either the Possible Identification or Possible Elimination confidence levels and/or the examiner does not believe a meaningful decision is obtainable due to various limiting factors.
  • POSSIBLE ELIMINATION: At least 80% of comparable words must be very dissimilar aurally and spectrally, producing not less than ten (10) words that do not match.
  • PROBABLE ELIMINATION: At least 80% of the comparable words must be dissimilar aurally and spectrally, producing not less than fifteen (15) words that do not match.
  • ELIMINATION: At least 90% of the comparable words must be very dissimilar aurally and spectrally, producing not less than twenty (20) words that do not match.

For more on Voice Identification, check out Ed Primeau’s latest book, “That’s Not My Voice!” available on Amazon.

 

photo credit: knitronica-87 via photopin (license)

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