Chill, obviously you are fired up about something, not my business. Investigators do write search warrants, I have written a bunch. The judge approves the warrant and it gets served. Some areas the DA will be involved but they don't have to be, most of the time it is a procedural thing. A search warrant is very easy to write and so long as you have probable cause to do the search the judge will sign it off. If you have it signed off, unless you lied on it, the court will bend over backwards to validate it during the court proceedings because the investigator when the extra step to get it.

As for the cop when you do a transport your job is to take that person to jail and not via the hospital. The last thing anything any cop wants to do it get to jail and find the person in the back seat is dead. Obviously the District Attorney had a hard on for the cops because they right away filed charges rather than wait for the completed investigation. Every cop knows if they go against policy then they will be disciplined up to and including termination. So if he was not seat belted in and it is in policy they, the cop, knows he is in deep shit. As to prosecution they also know the DA is out to get them so a good lawyer is important and hopefully he will stay out of jail. Once all that is done I am sure he will be sued civilly and then it starts all over again.