It took over 3 months for the DVLA to take action over a car that I reported to them as having no car tax. They actively encourage you to report a non taxed vehicle and when you do they do virtually nothing about it! When I complained about their inaction I just got a letter back stating there were things being done 'behind the scenes' and it was NOT an 'on demand service'. In the meantime the untaxed vehicle ( and therefore uninsured) was a menace to other road users. N.B. The Police are also powerless to act.