Turning technical possibility into legal proof
Authored by our legal expert, Justin Fitzsimmons.
Originally published in the September 2025 issue of Magnet Unlocked. Want to be the first to see new content? Sign up for our monthly newsletter, Magnet Unlocked.
When I first began trying cases, digital evidence wasn’t even part of the case. It simply didn’t exist in the courtroom. At most, you might see a phone bill or a stray email, but the real drama played out through eyewitnesses, physical evidence, and confessions.
That world is gone.
Today, the text thread, the GPS ping, the Snapchat screenshot, these are often the star witnesses. They don’t just support a case; they can decide it. And with that transformation comes a new responsibility; striking the balance between power and precision.
Every prosecutor knows the temptation. Faced with terabytes of data from phones, laptops, cloud accounts, and even vehicles, the instinct is to grab it all. After all, the proof of the crime must be hidden in that labyrinth of interconnected data. However, courts have made it clear that’s not good enough. A vague sense of “something useful must be in there” will not withstand judicial scrutiny.
Riley v. California (2014) declared that smartphones are vaults of private life, accessible only with careful judicial oversight. Carpenter v. United States (2018) raised the bar again, requiring a search warrant supported by probable cause and particularity when we seek location histories for more than seven days. The message is unmistakable; digital evidence may be robust, but overreach tips the scales toward suppression.
That balance begins not in the courtroom, but at the warrant stage. A well-drafted, data-driven affidavit is more than paperwork; it’s the foundation for admissibility. Define the scope with care, tie each requested data type to an element of the offense, and you protect both your evidence and your case.
Balance also shapes collaboration. Too often, prosecutors only join the case after the data has already been seized and analyzed, when it’s too late to address overbreadth, authentication gaps, or chain-of-custody missteps. The strongest cases I’ve seen are those where examiners, investigators, and prosecutors work in sync from the outset of the investigation. Together, they review the evidence, create timelines, and anticipate the courtroom challenges. Without that integration, even the most probative artifact risks exclusion or misunderstanding.
The case law illustrates the difference. In United States v. Vayner (2014), weak authentication evidence and testimony led to the exclusion of critical social media evidence. By contrast, in United States v. Browne (2016), coordinated circumstantial evidence and testimony secured the admission of Facebook chats. The distinction wasn’t the technology; it was the team’s foresight in balancing the digital evidence with the required testimonial authentication evidence.
The courtroom itself demands equilibrium. The technical accuracy of digital evidence must be weighed against comprehensibility. A spreadsheet of IP logs may be flawless, but it will lose a jury in seconds. An animated map can bring the narrative (or the victim’s account of the crime) to life if it is accurate, transparent, and tied back to admissible evidence. Oversimplify and you distort; overcomplicate and you lose the audience. The art is translation, not transformation.
Tool reliability adds another layer. Prosecutors carry the responsibility of demonstrating, through evidence and testimony, that a tool’s output is accurate, reliable, and admissible. State v. Anthony (2011) serves as a stark reminder of what happens when flawed parsing becomes the linchpin of a case; credibility collapses, and with it, the prosecution. Balance here means resisting the urge for speed at the expense of accuracy.
Looking ahead, the challenges only grow. Deepfakes threaten authenticity. Courts demand hyper-specific warrants. The scales of justice are shifting under the weight of digital evidence, and prosecutors cannot afford missteps.
For those of us who now work alongside digital forensics professionals, the mission is clear; ensure that every artifact introduced is not only probative but reliable and persuasive. Justice doesn’t depend on having the most data; it depends on having the correct data, handled properly, and presented with clarity. That is the balance prosecutors must master.
We’ll be exploring these challenges in depth through our new Legal Unpacked webinar series, which will dive deeper into the evolving relationship between law and digital evidence. Together, we can navigate this evolving landscape and find that balance—one case at a time.