Some thoughts:
I don't blame him for making them get a warrant. I wouldn't give mine over without one in this day and age of hacks and leaks.
And one lawyer suggested that he's made specific statements regarding what happened that have painted him into a corner in terms of how he can defend himself. There are pics of him on his phone right after the incident. The police may want to see if he texted anything that contradicts that.
No idea if it will be admissible if he's charged.