A federal appeals court has upheld a judge's refusal to throw out a lawsuit questioning a Ferguson police officer's use of force against the man who was with Michael Brown when that officer fatally shot Brown three years ago.

Tuesday's 2-1 ruling by an 8th U.S. Circuit Court of Appeals panel sided with Dorian Johnson in concluding that former officer Darren Wilson and ex-chief Thomas Jackson are not immune from such litigation. The court also found that Johnson sufficiently alleged that Wilson violated his rights, reports ABC News .

Johnson says that as he walked with Brown on a street on Aug. 9, 2014, Wilson illegally detained him by using his police vehicle to block their path. Moments later, Wilson fatally shot Brown during a struggle. Johnson fled and was not wounded.

Johnson insists in his lawsuit that Wilson "acted with deliberate indifference or reckless disregard" for Johnson's rights, used excessive force, and essentially detained him unlawfully by using his police vehicle to impede his movement.

The 8th Circuit on Tuesday agreed, with Judge Michael Melloy writing for the panel's majority that based on Johnson's version "the law was sufficiently clear" that "a reasonable officer in Officer Wilson's position would not have shot his gun."

The 8th Circuit's Roger Wollman countered that Johnson's movements were not illegally restrained by Wilson and that the lawsuit should be thrown out, likening Johnson's flight to that "of a moonshine-carrying" defendant.