But it referred to an appointment held on a Sunday, when that practice was closed.

Worse, it was dated six months after the doctor had retired.

I had called the practice the week I received the petition.

The receptionist was appalled.

She put me in touch with the practice administrator, who confirmed in writing that the doctor had not issued the letter.

The administrator also warned me that only a court or appropriate investigator could establish who made the document.

I had carried that response in my folder, hoping to use it at the right moment.