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Evidentiary Photographs – AFI-LLC - January 2022                                                     3 of 4

        original. For this reason, images should not be sent via email or added to a PDF file (Adobe) or PowerPoint (PPT) for
        review and analysis – or testimony. Why? These all compress the original file, which removes resolution and detail. The
        more times these files are opened and closed, the more minute details and resolution are lost. To age ourselves – if you
        can remember when every time you photocopied a copy, then a copy of a copy, each progression was distorted – this is
        what happens with digital images. JPEGs are compressed images – they are the most common, and as long as the high-
        resolution original is copied exactly, the file should be okay (TIFF is one of the best, uncompressed; same for RAW). If a
        JPEG is placed in a PDF, PPT or other – details are lost. Email sending and receiving will compress files. These manners of
        sending are okay for cursory reviews, where detail is not important and the overall image context is. It is best to have
        the habit of using full digital copy and transfer.

        Important – Different Image Formats
        It is further important to know what format was originally used in the original photographs – which may or may not be
        the files provided to you; or you provide to your client (and should be). If TIFF or RAW images are captured, usually a
        concurrent JPEG image is captured. TIFF and RAW images are many times larger, and are often used in homicide, child
        abuse, and sexual assault exams (together with Alternate Light Source – ALS – images; perhaps in another future
        commentary). As it happens, the December issue of Evidence Technology Magazine included an article with a video link
        specific to this issue – “Legal Information About Forensic Photography”. Secure Digital Forensic Imaging (SFDI) released a
        video specific to the legal chain of custody in forensic medical exams. Included are legal references for how to handle,
        store, and distribute photos during a medical-forensic exam as courtroom evidence. Here is the video link –
        https://vimeo.com/652161557  – and here are some key points from the video:
            - JPEG files are compressed versions of RAW Files. Most electronic health records (EHRs) cannot save RAW Files and
            they are important as they are the original files if photo authenticity is questioned in court.
            - Enhancement may further compress the already compressed JPEG image files that is derived from its RAW file,
            typically. Lossy double compressed JPEG images are not original.
            - Digital evidence uploaded to a server may result in legal Chain of Custody being lost [this may include law
            enforcement and prosecution]. Is there complete control of the digital evidence; or is it an IT team?
            - How long is uploaded digital evidence retained – months, years? The average retention is 6-8 years, and the
            destruction may be unknown to the agency. The statute of limitations is important – as are appeals and other legal
            matters which may further extend the need for longer retention – even decades.

        Retaining Photographic Evidence
        Specific to retention, we have had a case from post-conviction appeal in which all original digital evidence was
        destroyed, and the only retained evidence was the PPT presentations used for photographs (digital images). There was
        no ability to discern important details, and false artifacts of details were created by the pixelization of images. This was,
        in part, helpful in winning the appeal – demonstrating the conversions created false details. There is no reason for the
        source party to alter, delete, reformat or not give exact original copies to the opposing party. Most common, and in all
        of our related articles, presentations and courses, and also reports and testimony – we have cited why PDFs are not best
        evidence and only originals and their copies are. Any attorney or investigator given PDFs or renamed image files must
        demand exact copies of originals. Best Evidence is important to photographic images.

        One other issue we have too often, specific to photographs and videos, are the statutory and/or official agency’s policies
        to not release these due to potential public harm. We will discuss the reasons for the policies, and the problems created,
        in a future commentary.

        We hope this information is helpful to you, your cases, and your clients. Photographs – and videos – are worth a
        thousand words if they are captured, stored, analyzied and retained properly.













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