COMMISSIONER Charles Ramsey issued a memo to the Police Department in 2011 notifying officers that Philadelphians have the right to record, videotape or photograph them in public spaces.

But it seems that some of the cops missed that memo.

The American Civil Liberties Union plans to file a federal lawsuit Wednesday against the department after receiving complaints from city residents who claim that they were arrested and charged with disorderly conduct for recording officers in public, an act that the ACLU says is a First Amendment right.

"Clearly there's a pattern of Philadelphia police trying to discourage people from watching what they do by arresting them and charging them with crimes," said Mary Catherine Roper, staff attorney at the ACLU. "We're just not sure the message got through."

Ramsey issued the memo after a Daily News cover story highlighted several incidents in which cops wrongly arrested people for using their cellphones to record what they thought were violent arrests. In some instances, their phones and footage were destroyed. Ramsey declared then that it was not illegal to videotape an officer. Police spokesman Lt. John Stanford declined to comment, noting that he was not fully aware of the details of the incidents or the lawsuit.

Christopher Montgomery, a photojournalist and senior at Temple University, is the lead plaintiff in the complaint. In January 2011, Montgomery was waiting for a friend at 15th and Market streets when a verbal altercation between a group of youths and an older individual drew a crowd of onlookers. Several police cars arrived and Montgomery pulled out his iPhone to record the arrests.

Officer David Killingsworth, who is also named in the suit, approached Montgomery and said, "Put that away, stop recording," the complaint states. Killingsworth arrested Montgomery for disorderly conduct. The video he recorded was deleted. Montgomery was found guilty, but he later appealed and was successful. The suit lists at least five other such incidents in which citizens were arrested for recording police, including several reported by the Daily News.

"I felt a mix of fear, astonishment and outrage because my rights were violated," Montgomery said Tuesday. He hopes that the lawsuit will shed light on a major local and national issue. Roper said that the suit is intended to prompt more training and a cultural change in the department. She also hopes that the suit will prompt federal courts in Pennsylvania to state definitively whether citizens have a First Amendment right to record cops in public.