they can easily be erased. If they sent them to anyone that is a different story. There may be a record of it with the cell company.
If cell phone memory is anything like computer memory, deleting the image doesn’t necessarily remove the information.
If the phones are in police custody I don’t understand why they can’t get a court order to examine any evidence they might contain.
The cell phones and the car are currently being held by the San Francisco Police Department but have not been searched, according to Herrera.
http://www.nbc11.com/news/14982701/detail.html
Probably no chance of being able to erase the pix when they were running for their lives!