Why we built a biometric lock into Hawk's Evidence Locker

The problem nobody talks about until it's too late

When we first launched Hawk, the feedback loop made one thing crystal clear. People record driving evidence because they need it to matter. A dashcam is only useful if the footage survives long enough to be useful. But "survive" isn't just about file corruption or device failure. It's about the people in your vehicle, your family members borrowing your phone, or a moment of panic when you're worried about what the footage shows.

Continuous recording means your phone fills up with clips. Some are mundane. Others catch something that could prove liability in court. The problem: how do you know which clips are actually secure? We were writing SHA-256 integrity hashes to every single clip, which meant we could verify nothing had been tampered with. But verification doesn't help if someone deletes the clip before you ever get to check it.

That's when we started thinking differently about what "evidence" actually means. It isn't just data. It's data that's still there when you need it.

Fail-closed by design

The Evidence Locker isn't a folder with a password. It's a specific set of clips you've marked as important, wrapped in biometric protection that your phone enforces at the operating system level. Once a clip lands in the Evidence Locker, your fingerprint or Face ID becomes the only way in. Delete attempt? Your device won't process it without biometric verification first.

We chose biometric specifically because it's harder to bypass than a PIN. You can't guess it. You can't write it down on a sticky note. Your phone's secure enclave handles the verification, not an app running in regular memory. That matters when you're building something meant to survive a dispute.

The clips in your Evidence Locker also sync to your own iCloud account if you're on a Pro tier. They don't live on MRVL's servers. They live where you choose. That was a deliberate choice. We didn't want to be the custodian of your evidence. We wanted to be the mechanism that helps you protect it.

When a feature becomes part of the story

I remember the week we shipped biometric lock. Our support inbox had a message from a Lyft driver who'd been hit by a car that ran a red light. His phone had been on the dashboard. The driver who hit him had also been on a call with someone in his vehicle. During the 20 minutes it took for police to arrive, a passenger in the other car had somehow access to the Hawk app on the at-fault driver's phone and tried to delete the clip.

The clip was still there because it had been marked as evidence. The biometric lock didn't stop the delete attempt, but it did require authentication. The passenger didn't have the driver's fingerprint.

That's when I realised the feature wasn't abstract anymore. It was the difference between having a court-ready piece of evidence and having nothing. The police report was filed. Insurance settled faster. The Lyft driver's claim went through.

We've shipped a lot of small updates since then. Better GPS overlay. iCloud sync improvements. Trip map replay so you can see your route and speed from any clip. But the biometric lock stays exactly where it is: non-negotiable, on every piece of evidence you mark as important.

The manifest is just as important as the lock

Here's something most people don't think about until they're sitting in a police station or a small-claims court. The clips matter. But the proof that they haven't been tampered with matters just as much.

Every clip Hawk records gets a SHA-256 integrity hash. That's a fingerprint of the file's contents, written to a manifest that you export alongside your clips. When you hit the one-tap dispute export button, you're getting a ZIP file with your video, the GPS and timestamp overlay, and that manifest. A solicitor, an insurance adjuster, or a police officer can verify the clip's integrity independently. They don't have to trust Hawk. They don't have to trust your phone. The math checks out or it doesn't.

That's why the biometric lock and the manifest work together. The lock keeps the clips from being deleted or corrupted in the first place. The manifest proves they haven't been, if someone challenges you later. It's two layers of defence, both rooted in the idea that your evidence needs to be bulletproof.

What actually matters in a dispute

A few months back, a new driver on our community forum asked: 'Is this really better than just recording on my phone's camera app?' The answer isn't about the feature list. It's about what happens when you need the footage.

If you're recording on a standard camera app and someone deletes it, it's gone. No recovery, no proof it ever existed. With Hawk's Evidence Locker, the biometric lock means deletion requires your authentication. The SHA-256 hash means you can prove the clip was never touched. The one-tap export means you can send the manifest alongside the video, and anyone with a basic understanding of cryptography can verify nothing's been changed.

That's what builds trust in a dispute. Not features. Trust.

Rideshare drivers deal with chargebacks and false accusations constantly. Commuters hit by uninsured drivers. Fleet managers who need to protect their drivers from liability claims. They all came to Hawk for the same reason: they needed their evidence to mean something in court. The biometric lock is us saying: we understand what you're protecting, and we're not going to let someone delete it by accident or on purpose.