Adam Nossiter in the International Herald Tribune makes as clear as the facts allow why there is no mystery in the regime targeting the motorcyclists. As it happens, they are the "gun-wielding...assassins of police officers, politicians and others in this dusty city near the desert" that has moved "the authorities to declare that a radical Islamic sect thought to have been crushed by Nigerian troops last has been revived." The city is Maiduguri. The sect is Boko Haram. "Islamic law is in force here, as it is across Nigeria's north but not strictly enough for the sect."

On whose side is justice? Actually, on neither side.

The police, as symbols of hated government authority, are particular targets, as they have been during religious unrest in the past. But some killings have aroused particular fear because of the widening circle of victims.[...]
Dozens of Boko Haram members are still being prosecuted in the wake of last year’s attack. The mysterious death of their leader, Mohammed Yusuf, while in police custody remains unresolved. Memories of bodies piled up from last year are fresh.
“They were summarily executed; the authorities didn’t even listen to them,” said Abba Babangida, a merchant, across the street from the charred police station that was firebombed last week. “They just killed them. So people have to sympathize.”

Forgive me. But Nigeria is not a nation state (either.) It is a pretense the bloody reality of which was first exposed by the Ibos of Biafra in the late 60's. The pretense of of Nigerian peoplehood is sustained, as its was very crucially during the Biafran independence struggle, by pronunciamentos of the United Nations. The only people who believed these are fools.

My guess is that there is no justice whatever on either side in the battle between the regime and insurgents. They are both killers, killing for no humanitarian concern.