A federal appeals court says a lawsuit over the NYPD's sound cannons can go to trial. 

The suit maintains using the devices, also known as long-range acoustic devices, amounts to excessive force.

The lawsuit stems from the NYPD's use of the cannons during protests over the death of Eric Garner in 2014.

The six plaintiffs in the case say the devices caused them migraines and hearing damage during the protests.