The footage that erases itself
Most of the cameras that saw a vehicle-pedestrian accident belong to people with no stake in it. A deli, a parking garage, a bank entrance, a city bus, a delivery van with a dash camera - each keeps its recordings for a length of time it set for its own reasons, and then writes over them automatically. Nobody at those businesses knows an incident is being looked into unless someone tells them, and a routine claim notice does not reach them. By the time a file is opened in the ordinary way, a good deal of that footage is usually gone for good. Asking for it early and in writing is often the single step that changes what can be shown afterward.
What the scene shows, and how fast it goes
Where the vehicle came to rest, where broken glass and trim ended up, and where the person was found relative to the crosswalk are read together, and all of it disappears once the street is swept. If you or someone with you can photograph the vehicle, the roadway, the signals, and the sight lines from several angles, do that before anything is moved. Keep the clothing and shoes, the phone, the bag, and whatever else was being carried, unwashed and unrepaired. Witnesses usually give a name to an officer and then leave, so if anyone stopped, get a phone number directly rather than assuming it was written down. In many matters the person who was struck is in no condition to do any of this, which is why a family member or friend acting the same day matters as much as it does.
The police report and the medical record
A report is written quickly, from what was visible at the scene and from whoever was still able to speak, so it is not unusual for details to come out wrong: a direction of travel, a signal phase, a misspelled name, a witness left off. It is not the last word, and departments generally have a process for correcting a clear error or adding a statement, which goes better while memories are still fresh. Medical records work the same way, in that they exist only if you actually get examined, and injuries that feel manageable while adrenaline is up often read very differently the next day. If you declined transport at the scene, being seen soon afterward still creates a record, and some record is far better than none. When we are brought in early, much of the first work is preservation you would never see - letters to the businesses on that block, to transit operators, and to the insurer - rather than anything that looks like a case yet.
