Garde à Vue has to be seen a number of times in order to understand the sub-plots it contains. If you're not used to french wordy films, based upon conversation and battle of wits rather than on action, don't even try to watch it. You'll only obtain boredom to death, and reassured opinion that french movies are not for you.

Garde à Vue is a wordy film, essentially based upon dialogs (written by Audiard by the way)and it cruelly cuts the veil of appearances.

Why does Maître Martineau (Serrault) prefer to be unduly accused of being a child murderer rather than telling the truth ? Because at the time of the murder he was with a 18 years old girl with which he has a 8-years sexual relation. His wife knows it, she's jealous of it and he prefers to be executed (in 1980 in France, there was still death penalty)rather than unveiling the sole "pure and innocent" aspect of his pitiful life.