My wife's went up. The car was parked....
I can see why the insurance went up in your circumstance. The point I was making is that insurers will not be able to accurately assess the risk due to certain unknowns.
An incident in a car park when the car is unattended will leave these questions unanswered, and the fact that there is a correlation between accidents and claims, regardless of fault, means that insurances tend to go up! Hence the general perception on this thread.
However, where a no fault accident occurs with the potential for the innocent party to 'milk' the system, the insurance company can learn alot about the character of the client and adjust the premium in each case.
In our case, and the OPs, we were in the car at the time of the accident and therefore a potential injury claim could have been brought. The fact that no such claim was made means that the insurance company has new information which can be factored into the policy premium calculation i.e. no spurious injury claims expected from this policy holder.
Unfortunately in your case, although it was a no fault accident, the incident did not reveal any new information which could help the insurance company assess your risk, other than that those who have one accident tend to have more - hence the increase.
My original point, was that premiums do not always go up, rather than they never do. Hope this clarifies.
I suspect that the van driver mentioned in the original post may well see a significant increase in his premiums following the rejection of his claim for injury and loss. Although this would also be subject to whether he chooses to admit to this fact when renewing any private insurances, since the accident occurred in a company vehicle.
Regards, Neil