Bit of recent news.
I've just received an email from TomTom - regarding speed cameras in France.
It reads as follows....
Changes to the law in France
Since decree n°2012-3 was introduced on 3 January 2012, it has been illegal to be warned about the position of fixed or mobile speed cameras while you are driving in France. If your TomTom navigation device has the Speed Camera service and you continue to use it in France, you risk a fine of up to €1500
That's it.
It is illegal to use speed radar detectors in France.
However since all installations must be visible and there must be warnings of them, I don't see what their problem is.
Your radar device merely serves as a warning as their own notices of radar traps in the area does.
Since they only receive a signal, there is no way of telling if they are being used. Disconnect it if you see the French police and tell them you know about France but only use it in England which is full of radar traps. They have no right to confiscate it.