For many Lebanese, the best hope for answers about what caused the Beirut blast lies with French forensic teams and FBI investigators.

Lebanon’s judicial investigation of the Beirut port explosion started with political wrangling over the naming of a lead investigator, military threats to jail leakers and doubts over whether a panel appointed along sectarian lines could be fully impartial.

So for many Lebanese, their greatest hope for credible answers about the blast that wrecked much of their capital may lie with outsiders: the French forensic police who have joined the probe and FBI investigators are expected to take part.