How can I get access to traffic cameras?

On my way home from school I was pulled over, along with another car, for "Disregard to traffic device". I went straight in a right turn only lane. I have driven on this rode for many years now and just recently did they make the lane I was in a right turn only. (the area is under heavy construction and has been for a few years). After being issued the ticket, I asked the officer when they made the change, he told me it has been a right turn for months but because there previously was no sign, they were not enforcing it. I went back to the street to look for the sign. I found t clearly posted where you'd expect it to be, however when I drove past it ,moments before I was pulled over, there was a large truck (raised F-350 to be specific) parked in front of it. I assume the truck was part of the construction because a group of men standing behind it were taking measurements of the road. I would have taken pictures but the truck was gone by the time I returned. The intersection has cameras and I am wanting access to them to use as evidence. What do I need to do do get access?

Try an "Open Records Request".