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Warren Michigan Mayor Jim Fouts Voice identification test positive

December 22nd, 2016

Last week I received a phone call from Guy Gordon, a WDIV TVR NBC affiliate here in Detroit, Michigan. He came to the Primeau Forensics office, bringing with him a recording of an unknown voice making certain remarks. Mr. Gordon asked us to perform a voice identification analysis on the recording. The assignment was to determine if Warren Mayor Jim Fouts was the voice speaking in this recording.

Mr. Gordon also brought some recordings with known samples of Mayor Jim Fouts speaking, which I compared with the unknown recording. I performed two forms of voice identification testing (also known as speaker recognition) with a second audio forensic expert employed with Primeau Forensics. We performed both aural spectral voice ID as well as biometric voice identification testing. After analyzing the results of the testing, we concluded that the voices were a ‘probable match’. The biometric software came back with a high probability of a match between the voices across the majority of the tests. The aural spectral method also showed high consistencies between the voices with very little difference in their pitch. I was asked to interpret the results in percentage of probability and I reported an 80% chance that the unknown voice in the recording was that of Mayor Jim Fouts.

During a voice identification analysis, it is important that I stay unbiased and focus on the science of the investigation. I have no stake in the outcome of the testing and I make sure that anything I report is based on my data and analysis. This ensures that any other expert could perform the same tests and provide the same results.

It’s important to note that the test I performed would be considered a preliminary or ‘Emergency Voice Identification Test.’ The reason I call it an ‘Emergency’ test is because an immediate analysis was required and we therefore had to use any available sample of the suspected person’s voice to perform the comparison. In an ideal voice identification analysis, we would create what is called an exact exemplar. This is a recording of the suspected person reading the same dialogue as spoken in the unknown recording. In this test, we used both an in-person interview with Mayor Jim Fouts, as well as a radio interview found online. For the purposes of this test, we were able to obtain accurate voice information from the found samples. Creating an exact exemplar would lend further credibility to the analysis and results.

In many cases, an Emergency Voice Identification Test is the best option after the event in question occurs. Sometimes the suspected party is not willing to create an exact exemplar, and in some cases the client does not want to alert the suspected party of the testing until some results have been found. Threatening calls are especially difficult to deal with, as alerting the suspected person prior to any conclusive results can be dangerous. Providing these initial results can provide the company or client the support they need to take the proper steps forward.

In this case, the emergency voice identification test was the fastest way to get results so that other city officials could move forward. We performed all the available testing to compare the voice directly with known samples. My conclusions were based on the data and results that were calculated from the voice samples. By basing my conclusions on the data, I avoid as much bias as possible so that the results are objective. High consistencies were observed between the unknown evidence recording in question and the two sample recordings we had available. The pitch comparison, formant comparison, and biometric comparison all showed the same results which led me to my conclusion of Mayor Jim Fouts being a probable match to the voice in question.

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

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.

 

Audio Enhancement – When Do It Yourself Won’t Work

April 29th, 2016

Forensic audio enhancement is the process of removing unwanted sounds like static, HVAC fans, hums and other distracting background noise from a recording. The goal is to reveal or uncover the dialogue, conversation or ‘wanted’ sound in the audio recording.

There are two types of audio recordings that can be enhanced: analog and digital.

Analog recordings are those that have been created using some type of tape recorder. They may be old and likely have lost some of their audio fidelity. Tape noise and hiss may also be present, which are further examples of unwanted noise. Analog tape also has a short shelf life, usually 25 years, which quickly degrades the quality of analog recordings. When audio forensic experts enhance analog recordings in this format, the primary goal is to restore the lost or wanted sounds such as the dialogue and other pertinent events. A secondary goal that is accomplished through this process is the transfer of the audio recording to a digital format in a forensically sound manner. This ensures that no further degradation will occur to the file and provide a duplicate of the recording that is acceptable in court.

Digital recordings are audio recordings that have been created on a digital recorder, no tape is involved. Digital recorders store the recordings on an internal chip or removable storage device like an SD card. In this case, the primary goal of the audio forensic expert is to remove any unwanted sounds from the recordings like the issues mentioned above. The audio forensic expert will also preserve an exact duplicate of the evidence recording for their own records and for the court.

The big question that is always asked is ‘can my recording be enhanced?’ There are many situations where forensic audio enhancement helps reveal the events or conversations as they occurred. There are also times when an audio enhancement is unable to clarify the dialogue. The only way to tell is to test the recording in an audio forensic lab. At Primeau Forensics, we call this a preliminary analysis or investigation.

After 32 years of practicing as an audio forensic expert, my team and I have successfully enhanced hundreds of poor quality audio recordings to be used in litigations. The reason I am asked to perform so many forensic audio enhancements is because I have been extensively trained in forensic audio enhancement, I have completed and testified in dozens of cases and courts about my forensic enhancement, and I know the best tools to use for the forensic audio enhancement process.

Give us a call to learn more about our forensic audio enhancement services. 800.647.4281 or email primeauforensics@Gmail.com.

Three Tips to Successful Voice Identification and Speaker Recognition

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.

The Importance of Testifying – Three Tips from an Audio Forensic Expert’s Perspective

March 31st, 2016

The Importance of TestifyingAfter 32 years as an audio forensic expert testifying in dozens of cases on the local State and Federal court levels, I have gained experience and knowledge about the trial process.

Today, more than ever, many of my cases go to trial. Fewer criminal cases take a plea offer and even fewer civil cases settle outside the court room. I am spending more and more time helping courts understand audio evidence.

I chose to write about my court room experiences because I am often asked about testifying by our clients. Testifying is a very important aspect of my profession.

First off, testifying in court requires extensive attention to detail – both expected and unexpected. Testifying as an audio forensic expert requires an enhanced mental clarity, as the medium of audio may be interpreted subjectively, as well as objectively. My testimony as an audio forensic expert must be clear and precise, as well as simplified. It must include science, as well as opinions. It must also help the trier of fact understand the audio evidence for their decision making process. One excellent trial lawyer I previously worked with put it this way; I tell what is real and what is fake.

Tip #1-‘Preparation-The Key to Successful Testimony’

One of the most important elements of testifying is preparation. I always over prepare and insist our client lawyers schedule time with me before I get on the plane and in person before entering the court room to prep for trial. You can never be too prepared.

My preparation includes reviewing all work products, notes, reports and other expert depositions before going under oath. I also learn the client lawyer’s trial strategy and my role in that strategy. Preparation also includes anticipating cross examination.

Last November, I testified for the Attorney General for the State of New York in a negligent homicide in front of two Grand Juries. I had an agenda for preparation but my client lawyer had an even more intense preparation planned. We prepped my testimony for almost 8 hours over two days. There were 30 defendants and 8 defense lawyers. Since we anticipated cross there were no questions at all from any of the lawyers! Each one stood up and spoke (said) ‘No questions your honor’. Why? Because we did a great job preparing and anticipating cross; we brought out all questions on direct.

Tip #2-‘Look like an expert’

I remember testifying in Boston a few years back. Our trial team had two other experts one of whom I never would have guessed was going to testify. He did not wear a tie, his hair was a mess and his clothing was ill-fitting. I am not picking on this expert, but rather giving you a vision of what NOT to look like when testifying. On one hand, I shouldn’t be so judgmental, on the other hand, this is what a judge and jury do; judge!

One of the most crucial aspects of testifying is the expert’s appearance. First impressions are extremely important especially when you are going to testify in court in front of a judge, jury and opposing counsel. Your credibility is directly proportionate to the way you look. Unfortunately, in a professional environment such as a courtroom, pre-conceived judgment from the jury is more than likely to happen. You want to make the best, most professional ‘first impression’ possible. Forensic experts need to look conservative. Some lawyers will not retain a forensic expert with visible tattoos, piercings or radical haircuts.

Experts are paid well for their expertise; they should look the part.

Tip #3-‘Communicate with Conviction’

High quality communication is another ingredient to the success of your testimony. Not only does your communication matter for trial lawyers, but also your ability to communicate your findings to the jury is just as (if not more) important. When answering questions under oath, keep your answers short and to the point and resist the temptation to ramble on. Include scientific terms in your answers but make sure to simplify them if a juror’s body language implies confusion. Communicating with conviction also requires great eye contact. When answering questions, always begin your eye contact with the person who asked the question. Then while continuing to answer, make eye contact with the rest of the court room including the jury, judge and opposing council. One major mistake I often see experts make is answering questions with tunnel vision, staring only at the person asking the questions. It’s not a deal breaker but will reduce the impact of your words and testimony.

Testifying as an audio forensic expert with enhanced audio evidence can be difficult due to the potentially low court room acoustics and environment typically found in most court rooms. Enhanced audio evidence is perceived when played in the court room. The problem with playing audio in the court room there is no visual representation of what the audio is portraying. It is important that everyone in the court can hear and comprehend your audio evidence. This too is communication. Equally important is that your testimony has to be crystal clear in helping guide the jury to understand your science and opinions.

Aside from these three tips, focus on a healthy mindset. Make sure you get plenty of rest the night before. Drink a lot of water and eat healthy. A healthy mind set will contribute to a successful testimony. Testifying is stressful, but the key to success is preparation, appearance, and communication.

Los Angeles Times & Ted Rall: Forensic Video Response

September 11th, 2015

I was hired by the LA Times to perform a forensic audio investigation on a 2001 recording of a jaywalking citation being given to Ted Rall. The LA Times posted my results in an recent article to clarify the reasons behind Ted Rall’s dismissal from the paper. Ted Rall has since posted a rebuttal to this article on his blog, in which he made various claims about the results of my investigation. I would like to clear any confusion or misinterpretations about my forensic investigation and the results it produced. In the list below I have outlined points which I believe address the issues Mr. Rall published in his article:

  • I did not hear a crowd of people on the audio recording that I enhanced of former Los Angeles Times freelancer Ted Rall being ticketed by an officer for jaywalking.  I heard two people other than Rall and the officer talking on the recording.  At most, I could make out the word “jaywalking” being spoken by one of the two people.  I did not hear anything about “handcuffs” on Rall’s enhanced version of the recording or on the version that I enhanced.
  • We have an established chain of custody of this recording by the Los Angeles Police Department since officer Willie Durr recorded it in 2001.
  • We have no signs of tampering anywhere in the recording.  I found no evidence of tampering when I performed my authentication test.
I have created the following video to clear up these misunderstandings as well as clarify the actual results of my investigation.

Audio Enhancement: Removing a Single Sound

August 24th, 2015

Noise ReductionOne of the most common audio issues that I address during an enhancement is noise and other extraneous sounds. The noise floor is usually consistent throughout the recording and can be removed to varying degrees by using noise reduction software. The most complicated issues are the extraneous sounds that are not continuous. These sounds could include anything from a plane flying overhead to someone whistling while people talk. These sounds are difficult to pinpoint with standard tools like noise reduction and equalization, but they can be identified using a spectrogram.

A spectrogram shows both the frequency content of a recording and the level of those frequencies over time. It may be the most helpful tool to an Audio Forensic Expert because it visually presents everything that is happening throughout the audio in one window. Using this, the expert can both identify and address individual harmful noises in the recording. With the right software, these individual sounds can be selected and removed without affecting any other part of the recording. It is important to remember that there is a right and a wrong way to do this, which is why only a
trained Audio Forensic Expert should be hired to complete an enhancement for use in court.

When processing audio, it can be easy to introduce artifacts to the recording. Artifacts are unwanted noise that is produced from various processing and compression techniques. Considering the goal of an audio enhancement is to eliminate extraneous noise, introducing artifacts is the exact opposite of what you want when working with a recording. Many things can introduce artifacts, but the simplest way to describe the cause is over processing. By over processing, I mean using extreme settings within individual audio tools.

For example, I often work with audio evidence that is extremely quiet. This often requires a gain increase of portions where only voice content exists. If the gain is increased too much, it can cause clipping of the audio output. When this occurs, the edges of the waveform are essentially clipped off, producing a distorted and noisy audio signal. The end result is a less intelligible voice than the original, essentially defeating the purpose of the whole process.

When adjusting individual ranges of frequencies on the spectrogram, it is very important to be aware of artifacts. Being able to recognize artifacts and know the limitations of what processing can be done is what makes an Audio Forensic Expert necessary. When isolated portions are processed with a trained ear and the right knowledge, noise can be eliminated and voices can be brought out without introducing any artifacts.

I recently worked on an audio recording that had a siren present during a portion of talking. Because it was so loud, it made the underlying dialogue difficult to hear. Luckily, the siren could be isolated in the recording. By selecting only the siren and then decreasing the gain a moderate amount, the voices became more audible while still avoiding any artifacts.

Audio Forensic Experts have a plethora of tools at their disposal, which is making audio enhancements more and more effective. There are some things to be cautious of when enhancing audio, but any technique that helps should be used as long as the science is sound.

 

Ted Rall and the L.A.P.D – What Really Happened?

August 20th, 2015

Ted Rall

On May 11th, 2015, Los Angeles Times Freelance Political Cartoonist Ted Rall published an Op-Ed relating to an incident he allegedly faced with the LAPD back in 2001.

Rall claimed while being stopped for jaywalking in Los Angeles, an officer of the Los Angeles Police department assaulted him. Rall included descriptions of the officer throwing his driver’s license into the sewer, being thrown up against a wall, and being handcuffed. Rall went on to describe a crowd of onlookers surrounding him during this event, asking officers about the legitimacy of the arrest.

In response to the post, the Los Angeles Police Department presented a 14-year-old recording of the event. Based on this recorded evidence, Rall was fired from the L.A. Times. Since then, Rall has disputed the LA Times and has produced both an enhanced version of the audio and a transcript of what he believes can be heard in the recording.

The L.A. Times commissioned Primeau Forensics to examine and enhance the audio recording provided by the L.A.P.D. The audio evidence was analyzed with the goal of uncovering the events as they occurred. Primeau Forensics holds no bias toward either party and approached the investigation as such.

You can hear the enhanced audio recording below. Read Primeau Forensics’ transcript of the confrontation here.



				

Audio Forensic Synchronization – What Happened When?

June 24th, 2015

Audio Forensic SynchronizationGenerally speaking, any device that captures video is also capable of simultaneously capturing audio. This audio can be crucial to the Forensic Expert, as it can show the expert more clearly “what happened when,” when it comes to a crime scene.

Picture this: a young man has just assaulted an older woman, and a police officer is in pursuit. As the young man begins to run from the police, another man on the street begins shooting video from his cell phone. The police officer is recording from both the police-car dash-cam, along with a body-worn camera, which he switched on when he began his pursuit.

As the young man continues to run, the officer announces “Taser!” and fires, activating the camera built into the officer’s stun gun. After sprinting around a corner, the young man is found dead. How did this happen? Who was responsible? When did the death occur? This is where audio can come in major handy.

As the appointed Forensic Expert, you are tasked with determining what you believe happened in this situation. The evidence available to you includes the cell phone video from the witness, the police officer’s dash-cam, the on-board camera from the taser, and the body-worn camera.

This is where your audio comes in handy, as it allows you to synchronize the audio in chronological order. Begin with the event that took place the earliest. In this case, it would be the police officer’s dash-cam, as it is always running. Next, find the portion of audio that starts the witness’ footage. Listen for a certain sound or yelled phrase for reference, and when you find that sound source from the officer’s dash-cam video, you’ll know that this is where the witness began recording.

This can also be done by visually inspecting the waveform. Large, quick spikes in the level can make it very easy to quickly sync the audio. Most software will also allow you to zoom in closely on the waveform so you can line the waveforms up as closely as possible.

Next, you’ll want to find the point where the body-cam began recording. Again, this will require critical listening and visual analysis to align the sounds from the body-cam evidence and the witness video to get an idea of when the officer began recording.

From there comes the last piece of evidence: the taser camera. Remember when the police officer announced “Taser”? Well, the second the trigger on that stun gun is pulled, the in-board camera kicks on. The body-camera audio will give you an idea as to when the officer announced his stun-gun use, along with when the video clip begins.

This will give you the most accurate occurrence of events. The actions of the taser camera are the most recent recording of the event, and in it you notice a loud sound that couldn’t be heard in the other recordings. That sound was the sound of a pistol, which another officer around the corner pulled out to shoot in an attempt to detain the criminal. This is what the body-camera, witness video and dash-cam, did not see. However, due to the alignment of the audio, the expert is able to see, in chronological order, the events as they occurred.

Synchronization does not always go so smoothly. Sometimes different frame rates are used in different videos, which can alter the speed of how the different videos play back. Most modern digital recording technology is self resolving and does not have this issue, but there are still devices that do not. These can cause the video and audio to be in sync at one point, but slowly drift apart throughout the video. It’s important to be aware of this so adjustments can be made to make sure that all the events are synchronized as accurately as possible.

The audio makes it much easier to synchronize all of the pieces of evidence together. The audio can provide both auditory and visual cues, through viewing the waveform, to use as reference points so an accurate sync can be completed. With only video, the different perspectives and qualities would make it extremely difficult to find exact reference points to line up.

Not all cases will give the expert this much to work with, but when working with multiple clips of the same occurrence, having a critical ear can be invaluable to understanding the timeline of the situation. Video can be powerful, but its direct counterpart, audio, can be essential to finding the cause of confusing and misleading investigations.

Visual Inspection

April 21st, 2015

visual inspectionSound waves can tell us a lot about a recording. Like metadata, the visual elements of a sound wave can expose characteristics of an audio recording without even having to listen to it. These characteristics can be important, especially when it comes to detecting edits within audio evidence. The process of observing these characteristics is called visual inspection.

Visual inspection (a general term that comprises a variety of forensic tests like narrow band spectrum analysis) is a crucial part of an Audio Forensic Expert’s job. To understand how crucial visual inspection really is, it’s important to understand the concept and value of the noise floor.

The noise floor (usually unwanted sound) of a recording is the present background noise and overall “ambience” of a recording. For example, if you’re recording yourself speaking on the street in New York City, and you’re speaking into a microphone while standing in one place, the sound of the cars going by, the conversations happening around you, and the overall city noise (unwanted sound) will contribute to the noise floor.

If you’re standing in one spot recording that audio, the noise floor will never change, because the environment your audio device is picking up will stay consistent the entire time. The second that noise floor is altered;you know you have an edit.

There are many ways to examine this. One of the most reliable ways to observe this noise floor is what’s known as a spectrogram. The spectrogram is meant to read the spectrum of an audio recording. To put it simply, a spectrogram takes the contents of an audio recording and conforms the characteristics to blends of color that represent the spectrum of an audio recording in Hz. You can see that below.

Now, because the noise floor of a recording never changes, you can tell when you have an edit when the spectrogram shows a change in, or absence of, color. The noise floor will always stay consistent, so when there’s a short drastic change such as the one pictured below, you know you have an edit. This makes the recording inauthentic.

Spectrogram edit circled

Surely there are other ways to visually detect edits. Even the sound wave itself can expose an edit.

All sound waves should be smooth and continuous. Even if someone were to loudly clap during an audio recording, the sound wave will still remain smooth and continuous. When you see gaps, or a wave that is not smooth and continuous with another piece of the audio file, you know you have an edit.

Though a critical ear is generally considered the most important part of Audio Forensics, a good eye for edits in visual inspection can teach you a substantial amount about the evidence you’re working with before even taking the time to listen to it. Visual inspection really comes in handy when trying to determine the authenticity of a piece of audio evidence and to make sure a proper chain of custody was kept throughout the distribution of audio evidence.