It doesn’t matter if police think you were texting before you caused that crash, they can’t legally seize your cell phone.
He says if they do arrest you, then, as a search incident to your arrest, they can.
“They could get a subpoena for it if they could get a court order,” Tritico says, “But, just because they want what’s on it does not give them the right to take your personal property.”
The story is the same if you’re shooting video at a crime scene. Tritico says the police could always ask nicely, saying they need your video for evidence.