My question involves a traffic ticket from the state of: CA
When I was commuting to work in the morning I was cited by an officer under 21658(a) Unsafe lane change on I-580. He cited me when I was trying to change the lane to my right. I was next to the fastest lane when I tried to switch the lane. I was still within my lane, I just turned the wheels of my car around but still was not in the other lane and one of the trucks coming from behind in the lane where I was switching to, honked just to caution me. Also my speed at the time was around 20 mph. Based on the honking by truck officer must have thought that I did the unsafe lane change and he cited me for this. Officer was in the fastest lane (to the left) and and approximately 5 cars behind me, so I am not sure how was his visibility to this event.
Now for above situation, I am taking on trial by written declaration, I have following questions,
1. How do I prove that I plead not guilty, since I have no proof and it is purely situational
2. What should I write in my defense
3. If I want to get officer notes to strengthen my case, how do I request it?
4. Any other advise for making my case stronger would be really appreciated
I really appreciate everyone's help in the forum,

