Can you be fined for putting a "For Sale" sign in your car window and leaving the car on the road outside your office? Unfortunately, one car owner did not ask that question and ended up with a 100 pound fixed penalty notice! The car owner was accused of "offering goods for sale in a parking place". The fact that his car was fully taxed and insured was irrelevant.

When he phoned the council, in this case the North London borough of Barnet, he was informed that the offence had been introduced 12 months earlier and had been advertised in the local Barnet paper. But as he did not live in Barnet, and did not read the local Barnet paper like most other people in London, he had not seen the advertisement.

We have all seen private "For Sale" notices on car by the road side - some have even been on the verge alongside roundabouts, so it is difficult to believe it can be an offence. And why is the "For Sale" sign any different from a driving instructor's car that has the name and details of the driving school on the side? Surely the instructor is offering goods for sale. Surely if the car for sale notice is offering goods for sale, so are virtually all commercial vehicles.

The owner of the car, an estate agent, lives in North London and works each day in Finchley. He decided to sell his wife's T-registered Ford after he was offered a newer Vauxhall by a friend. A month later he printed A4 sign at the office reading: "Ford Escort XL, many extras, low mileage, wife owns. Price negotiable" and put his mobile number at the bottom.

The following day, having left the car in a side street near his office, he returned to discover the offending penalty ticket. He immediately replied to Barnet Council explaining his objections and phoned three days later to confirm the Council had got his letter.

The Council told him that the new regulations had been introduced about 12 months prior and it had been advertised in the local paper. But since he only worked in Barnet, he had not seen the notice in the paper. "What happens to all the other people like me who don't live in Barnet and don't know about it either? Is everyone going to get a ticket?" he asked.

Having given up roadside advertising he is now selling his car through a local garage. But he is waiting to receive a formal response from Barnet Council before deciding whether he will pay the fine.

A spokesman from the Council said the rule, called "New parking Contravention Codes ", was brought in to keep parking space free for residents. The code was introduced with the description of "using a vehicle in a parking place in connection with offering for sale, or sale, or exposing for sale, the goods when prohibited".

The spokesman went on to say that the council's position is that they do not encourage or support trading from the public highway. This includes offering cars for sale. However the council is undertaking a review of this policy and will make a decision as to its future after all of the options available to support our corporate priorities have been considered. Hmm, I think the estate agent from North London will still have to start saving his 100 pounds!