Article title is: The British Secret Service and the escape of Sir Sidney Smith from Paris in 1798.
Anyone with an interest in Sir Sidney Smith should enjoy this article. Goes into detail how Sir Sidney was involved in the British Secret Service (which is news to standard biography of Smith) Prior to this recent 2002 article, everything I've read about Smith's escape from the Pairs Tower Prison states that it was the work of local loyalist's. As it turns out, it was the British Secret Service that planned, organized, and financed the escape. The article also explains that it likely was the need to cover up the involvement of the British Secret Service that prompted Sir Sidney to build up his story after the escape.
This means that the French were absolutely correct in not holding Sir Sidney as a POW; he was indeed a spy after all.