Have you come out with any allegation that the police deleted the video? That seems to be the case from reading between the lines . . . am I mistaken?
I don't know who deleted it.
My camera had lots of photos and video on it when Officer Dilley confiscated it. He later told me that the county jail would not accept my belongings because I was being "booked as a John Doe" so he would place my belongings in "safe storage" there at the airport police department. Officer Dilley and I left the airport around 4:30 p.m. Sunday without any of my belongings except for those on my body. I was released around 10:00 p.m. Monday. Tuesday morning, I returned to the airport police station, explained the situation, and requested my belongings. The officer I spoke with retrieved my two bags. I took a quick look, found the most important things to be there, thanked him, and left. In the hallway just outside the door to the police, I removed my camera from my bag, powered it on, and found that it reported "no images". I immediately returned to the police and reported that my camera had been tampered with while it was under their control and that images were missing. The officer told me he had not been involved and that I could file a report. There is a record of my contact with him and my claim that someone tampered with my camera in the police file.
It's often possible to "undelete" a file from a computer disk. In a nutshell: With most computer file systems, including that which most cameras use on their memory cards, saving a file causes the data to be written somewhere in a pool of "unused" space, then the name of the file and the location of the data within that pool are recorded in an index. To read a file, the computer looks up the index, then goes to the location of the data and reads it. To delete a file, the computer removes the index entry and marks the space where the data from that file was written as unused. It doesn't actually overwrite or erase the data, so until something new is saved that overwrites the data from the "deleted" file, it's all still there.
I ran some forensic analysis software on the memory card while I was on the plane flying home. Finding that video among the recovered items and watching it for the first time was one of the most joyous moments of my life.