ACLU attorney Taylor Pendergrass said trial testimony of some of the protesters has uncovered questions about whether police gave an order to disperse before the arrests on Aug. 25. The request for investigation was filed with Denver's independent police monitor, who oversees reviews of police shootings and citizens complaints.

Police spokeswoman Sharon Hahn said Friday she could not comment on the request because she hadn't seen it.

Independent police monitor Richard Rosenthal confirmed the ACLU filed a complaint and asked for a review, but said he could not comment.

Pendergrass said police supervisors have testified that no dispersal order was given before the arrests, contradicting testimony by officers who say protesters disobeyed the order before their arrests near Denver's 16th Street Mall.

Pendergrass said in the complaint the testimony raises questions about whether police violated their policy of giving people a chance to disperse before making arrests.

On Thursday, Denver jurors acquitted three protesters who had been accused of blocking a street on Aug. 25.

Police arrested more than 150 people in Denver in disturbances related to the convention between Aug. 23 and Aug. 28.

About half have plead guilty, while others are contesting their charges, with some cases set for trial through January.