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Where a Enforcement Authority believes that a moving traffic contravention has occurred, it may serve a Penalty Charge Notice on the person appearing to them to be the owner of the vehicle. This is...
from the "Charge certificate" paragraph to the end of the page.
In short, once the debt has been registered with the Traffic Enforcement Centre you can file a statutory declaration on the ground that "
You made representations to the Enforcement Authority concerned but did not receive a Notice of Rejection from that authority".
You don't want to rely on the post, so once the 14 day period has expired, check the council website every few days for the outstanding amount, once the debt has been registered it will go up by a further £9.
At that point you can print off form PE3 from
Form PE3: Challenge an unpaid penalty charge notice.
and go and get it sworn at the local county court, then scan or photograph it and email it to tec@justice.gov.uk with the PCN number in the subject line.
Any questions please ask.