On Monday, his brother's trial opens under tight security in Paris, where he faces charges of helping to plan the deadly assault.
Abdelkader Merah is the first to face a trial arising from the wave of Islamist attacks that have buffeted France in recent years.
The killings by Mohamed Merah, 23, the first Islamist attacks on French soil since 1995, marked a new form of terror -- acts carried out by an isolated individual.
Judges now want to determine the exact role of his 35-year-old brother Abdelkader Merah, who stands accused of "knowingly" helping to facilitate the "preparation" of the attack, in particular by stealing the scooter used for the three separate shootings.
He will appear alongside 34-year-old Fettah Malki, accused of giving Mohamed Merah a bulletproof jacket, an Uzi submachine gun and the ammunition he unloaded on his victims.
Neither man denies giving Merah the items, but both have claimed they were unaware of his intentions.
Abdelkader Merah faces a possible life sentence while Malki could get 20 years in prison.