Bruno Waterfield seems to have found the smoking gun in the Telegraph this morning.
"Working from home" seems to have required a new meaning in Brussels.
Mr Dover said: "Everyone agrees that I am not breaking any of the parliament's rules. I want to get on with my job of representing voters here in my constituency, not talking to the media about this."
He uses a family-owned company, M P Holdings Ltd, as the "service provider" for secretarial and parliamentary assistant work paid for by the parliament, currently worth more than £160,000 a year.
He declared "no financial interest" in the family-owned firm that employs his wife, Kathleen, as secretary and daughter, Amanda, as part-time parliamentary assistant. Both wife and daughter are also company directors.
Since 1999, £271,692 has been paid to the directors. In 2007, company accounts, registered in January 2008, show that the "director's emoluments" were £60,000.
Mr Dover said: "They get market rates, but they put in two or three times the number of hours – they just never stop, and I pay tribute to their hard work. Therefore I am totally innocent of any charges."
But the parliament's register of assistants shows that they are not accredited to enter or use official buildings in Brussels or Strasbourg.
As well as earning between £20,000 and £30,000 as a part-time parliamentary assistant, The Daily Telegraph has learnt that Amanda Dover, a "fully qualified secretary", works a four-day week as a travel agent in Radlett, Herts, close to her home.
Mr Dover said: "They work as and when required. A lot can be done on the internet, over the wires so to speak."
Chris Davies, a Liberal Democrat MEP who has called for reform of the expenses regime, has highlighted Mr Dover's arrangements in his campaign.
"I doubt that Den Dover has broken any parliamentary rules, but this simply highlights that there is something very wrong with the rules."