Can a cop do this

[daisaw1219]

Well i got a ticket for a unsafe lane change in NJ....This is BS....the cop said i cut 2 lanes withouth signaling.....Well i was driving down the highway and i was behind a truck with rocks hitting my car soo i cut to the left then i cut again to the left after about 10 seconds becasue there was a super slow minivan doing about 50mph in a 65zone...Then I passed the cop and he pullls me over for unsafe lane change that he could not see....After he takes me license he gives me a warning ticket for speeding saying i was well over 90mph in a 65zone and then he preceeds to tell me im lucky to get a unsafe lane change and tells me if i go to court he has 30 days to issue additional tickets.