Poirot's Poirot’s police years

"Gustave was not a policeman. I have dealt with policemen all my life and I know. He could pass as a detective to an outsider but not to a man who was a policeman himself." — Hercule Poirot in "The Erymanthian Boar" (1940).

As an adult, Poirot joined the Belgian police force. Very little mention is made in Christie's work about this part of his life, but in "The Nemean Lion" (1939) Poirot himself refers to a Belgian case of his in which "a wealthy soap manufacturer poisoned his wife in order to be free to marry his secretary". We do not know whether this case resulted in a successful prosecution or not; moreover, Poirot is not above lying in order to produce a particular effect in the person to whom he is speaking, so this evidence is not reliable.

Inspector Japp gives some insight into Poirot's career with the Belgian police when introducing him to a colleague:

"You've heard me speak of Mr Poirot? It was in 1904 he and I worked together – the Abercrombie forgery case – you remember he was run down in Brussels. Ah, those were the days Moosier. Then, do you remember "Baron" Altara? There was a pretty rogue for you! He eluded the clutches of half the police in Europe. But we nailed him in Antwerp – thanks to Mr. Poirot here."

Perhaps this is enough evidence to suggest that Poirot's police career was a successful one.

In the short story The Chocolate Box (1923) Poirot provides Captain Arthur Hastings with an account of what he considers to be his only failure. Poirot admits that he has failed to solve a crime "innumerable" times:

"I have been called in too late. Very often another, working towards the same goal, has arrived there first. Twice I have been struck down with illness just as I was on the point of success."

Nevertheless, he regards the case in "The Chocolate Box", which took place in 1893, as his only actual failure of detection. Again, however, it must be stressed that Poirot is not reliable as a narrator of his personal history and there is no evidence that Christie sketched it out in any depth.

It was also in this period that Poirot shot a man who was firing from a roof onto the public below.

Poirot has retired from the Belgian police force by the time that he meets Hastings in 1916 on the case retold in The Mysterious Affair at Styles.

It should be noted that Poirot is a French-speaking Belgian, i.e. a Walloon; but there can hardly be found any occasion where he refers to himself as such, or is so referred to by others. At the time of writing, at least of the earlier books where the character was defined, non-Belgians such as Agatha Christie were far less aware than nowadays of the deep linguistic divide in Belgian society.