Westminster Council generated the most money from fines in 2007
Parking fines generated more than £650m for London councils over the past three years, figures have shown.
But the statistics, obtained by BBC London, revealed the amount raised in 2007 was down £7m to £216m.
While 21 councils saw parking fine revenues go up in 2007, nine, including Camden and Lambeth, two of the top three, saw a drop.
Westminster had the highest figure of £41m while Greenwich recorded the lowest at £1.7m.
In 2007 Westminster Council began using high-tech cars which use a CCTV camera in a periscope to enforce traffic and parking restrictions in the West End.
Paul Watters from the AA said using CCTV to enforce parking regulations was not a completely fair system.
"CCTV isn't particularly fair, it's only fair if drivers are warned that the CCTV is being issued and that the local authority is doing something about the problem that causes so many tickets to be issued," he said.
He explained that new guidance from the government means authorities will have to produce accounts for parking fines, starting from the end of the year.
"Hopefully it should be a bit more transparent and we should be able to start singling out the bad authorities from the good ones," he said.
But Westminster Council said all money made from parking fines was used to finance transport projects such as the Golden Jubilee Bridges and the Bishop's Bridge.
Councillor Danny Chalkley said: "As a local authority... we are legally not allowed to make a profit from our parking services.
"Every single penny of surplus income collected from parking in Westminster is ploughed straight back into major transport projects."
He added: "The use of cameras...has made enforcement fairer, more transparent and accurate and can be used in areas where there are known issues with traffic flow."
There were no figures available for two London councils.