E47: Season 5 Episode 2 – Using Video in an Evidentiary Setting

by Nov 10, 2020Season 50 comments

Tom Dunlap chats with David Notowitz, of National Center for Audio & Forensics, and David Ludwig, of Dunlap, Bennett and Ludwig, about how much information is stored in digital evidence and why attorneys need to thoroughly analyze video and audio files the way they do other documents. We also discuss what can go wrong if attorneys don’t do their homework with digital evidence. 



National Center for Audio and Video Forensics 


David Notowitz founded the audio, video, and digital file forensic company known as the National Center for Audio and Video Forensics to help attorneys better understand digital evidenceDavid explains that whenever an attorney has a client with video evidence, whether on the cell phonesurveillance, or body camera, Go Pro videos etc., that attorney will send it to them to clarify, enhance, and analyze. This is key as video and audio evidence is not always what it initially appears to be, which can heavily influence how a case plays out.  


Deep Fakes and CODEC  


When they receive a piece of evidence, David and his team must look at the metadata—the data that is embedded in the file that can reveal creation date, modification date, setting, time, and much more. The metadata also reveals what format was used to create that file, and elements such as frame rate and resolution. This metadata is important as it can shed light on what type of device that video came from, which allows the, to cross reference and confirm if that file is original or a tampered replica.  


Sometimes, David and his team will receive a CODEC, or a file that has been compressed and then decompressed, which occurs when a file is saved in a certain way and either emailed or texted to another person. With the CODEC, they can hopefully locate the original file, which is much easier to analyze and obtain more accurate information from since elements like resolution are affected during compression and decompression. This ability to track a file is essential, particularly when dealing with deep fakes, or evidence that initially appears solid but is actually misrepresentative once the metadata is examined.  


Overall, David seeks to help attorneys verify authenticity in digital files, and to find clarity about what they have in front of them. NCAVF can help attorneys analyze frame by frame, which garners so much more information than simply watching footage. David points out that if you, as the lawyer, do not thoroughly analyze the evidence given to you, the other side may, and you will have nothing with which to combat that.  


Listen to the episode to hear more about why this is imperative in court.   



Text Chains  

Next, David speaks on how important it is to verify a text chain. He urges lawyers to never accept paper versions, as those could have been easily altered, with messages erased. He encourages attorneys to obtain the original cell phone and bring it to a center like his own, where they have experts who can extrapolate the entire cell phone data. With this, you can see signs that something was deleted. He does point out that most of the time, things are usually not deleted or messed up on purpose—most of the time, emailing or texting evidence alters the file. 



Three Things every Lawyer Should Know  


When it comes to digital evidence, David outlines three things that every lawyer should do and know. The first one is that most attorneys don’t spend the time they need to analyze the digital evidence the way they do with physical evidence. He encourages lawyers to treat the digital evidence with the same seriousness as they do with transcripts, documents, and police reports, as digital evidence can make or break a case.  


The reason for examining digital evidence with the same significance as other documents is that just because something is a video, does not always make it true. Still frames can be misunderstood or misinterpreted. Listen to the episode to hear an exciting and interesting court story from David.  


The last point David stresses is that attorneys don’t always realize how much data they can extract from the digital evidence. Imperative information such as height, speed, difference, or how a lens can distort the information can pivot an entire case.   


Same Photos, Different Data  


David tells one last story to relay a significant message. When looking at a subpoenaed phone, they discovered multiple photos that looked the same. However, when they looked at the metadata, each photo had completely different metadata – this revealed an inconsistency with the dates that the prosecution team claimed certain events happened. The photos revealed that those events captured on the phone actually took place several months in advanced, and therefore, had no relation to the case at hand.  



Always Question 


David leaves us with his main lesson: always question what you are given. He urges attorneys to never just accept digital files as the pure truth—diving into the metadata can reveal that key evidence is, in fact, misconstruedOverall, every attorney should question the media evidence they receive and to allot themselves enough time and money to go through it properly.  


David Notowitz BIO: David is the founder and lead audio, video, and digital forensic expert of NCAVF, the National Center for Audio and Video Forensics. NCAVF provides all levels of consulting, video and audio clarification, and media preparation for legal situations – from video production, 3D scene reconstruction, and forensic measurements to media enhancement, cellphone recovery and analysis, and testimony as an expert witness. From 2001 until today, NCAVF has grown into one of the top privately owned audio, video, and smartphone forensic companies in the country with six full time employees.


Tom Dunlap: LinkedIn 

Blackletter: Website 

Dunlap Bennett & Ludwig: Website 

David Notowitz: LinkedIn

 David Ludwig: LinkedIn  

National Center for Audio & Forensics: Website


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