Which is the default past to use in modern literary translation?

Question

Today, in 2018, when translating some piece of fiction from a foreign language into French, which tense would be normally used for the past tense of the foreign language: Passé simple or Passé composé? Would perhaps either feel "all right" to the readers, or one of them feel too archaic/formal, or the other too conversational/informal?

I'm looking at a new translation of Agatha Christie's "The Murder of Roger Acroyd" (traduction nouvelle de Françoise Jamoul) and it starts out using passé simple from the get-go. I'm curious as to why, and tried to come up with possible reasons - don't laugh too hard if some of them are ridiculous...

1. Is it because this is an old novel, and so a linguistic style compatible with its age is appropriate? Would a modern detective novel translated from English use passé composé?

2. Is it because this is the appropriate choice for a literary text, even a detective novel, and the use of passé composé would be too informal?

3. Is it because English, particularly, employs widely both simple past and present perfect, and to distinguish them two French tenses are customarily used, even though this doesn't reflect contemporary conversational usage?

Answer 1

#3 is certainly wrong. The difference between passé simple and passé composé is not at all the same as the difference between simple past and present perfect. Passé simple and passé composé are pretty much interchangeable with regards to meaning. You can take any sentence and switch between the two, it will mean (almost) the same thing (with some differences in subtext, passé simple is for more distant past). This isn't the case for simple past vs present perfect, often you can't even do this switch and keep a meaningful sentence.

Passé simple is simply the tense used for literature, even if orally nobody uses it anymore. "Even" for detective novels (although I'm not sure why detective novels would be "less formal"), passé simple is the tense of choice. It has nothing to do with the age of the novel.

However, even for literature, passé simple is starting to decline somewhat. Book meant for children/teenagers are starting to be written in passé composé: famously, the new translation of The Famous Five is written with passé composé. Younger people tend to write their autobiographies using passé composé, apparently. Other than that, using passé composé would probably feel informal to most (adult, I guess) people.