If (once) summonses are served you will need a solicitor.
You will almost certainly get points on your licence and a fine.
michaelm said:
Really? Can you get points for non display of Tax? I thought penalty points could only be issued in relation to safety . . anything else weakens a points system which should be solely about road safety.
Yes, really. It's not just a non-display offence. OP signed a form declaring his vehicle off road and then used it while the declaration was in force. There was no tax disc and the vehicle was untaxed at the time of detection. That's three offences so far, and the most serious offence, which supercedes any safety considerations, is apparently attempting to deprive the State of revenue through a false declaration.