This comment does not relate to congestion charging which is already happening with the specific aim of reducing congestion in cities, or to totally privately funded highways, bridges or tunnels where the investment will be recovered by tolls. This is about charging for the general use of the highways network, which is most likely to take place on the Strategic Road Network (SRN).
The SRN, as it exists now, has been funded by the taxpayer/motorist, so the road user is going to be charged for using a highway network they have already paid for, which does not seem at all fair.
We already have an existing fairly fool proof method of collecting 'road charges' - the Fuel Excise Duty (FED). If you have high mileage you pay more tax, if you have a big posh gas-guzzling car you pay more tax. The present system seems entirely fit for purpose. I know people do not like paying this tax, but does the road charging lobby really think the motorist will be any happier paying a separate charge for using the SRN, when a significant portion of the FED will have to be retained as general taxation.
Only about one third of the FED is spent on roads, and you will still need a substantial amount raised by FED to pay for the maintenance of the local road network, which I am assuming will not be covered by RUC.
It may be relevant to mention that the M6 toll road has never been viable, while there has been a free option available, the local highway network will get increased use, and will need increased maintenance.
If the argument is that the charging will be for the upkeep of the SRN, then somebody has to do some serious study as to the cost of setting up a system to facilitate road charging related to the amount of money received in charges. The amount of money, many millions, to set up the road charging infrastructure and the back room IT and the data storage facilities will be a substantial initial cost, with a continual maintenance cost to the road user.
We will also have the unpleasant 'niggles' in the system, the small but important things that will really upset the public, such as number plate theft and number plate cloning. This is already a fast growing crime. It is the innocent victim of number plate theft or cloning who has to establish his innocence quite quickly or he/she can be in for some serious consequences.
Concern for the green benefits of RUC are tenuous in my opinion and ignore the carbon footprint of an additional unnecessary layer of highway infrastructure. And there is no reason why the same benefits could not just as easily be achieved by increasing FED.
In my opinion what is really needed are more highway engineers and people who know how to maintain a highway network far more cost effectively than it is being done at the moment.