The National Press Photographers Association (NPPA) has sent a letter of complaint to the Baltimore Police Department expressing concern after police threatened to arrest a citizen videotaping police conducting an arrest, according to the Baltimore Sun and the NPPA Advocacy Committee. Ironically, the incident occurred less than 24 hours after police issued new rules instructing officers not to "prevent or prohibit" people from photographing or taping police actions, another article in the Sun said.

In the letter, addressed to Baltimore Police Commissioner Frederick H. Bealefeld III, the NPPA noted that "photography by itself is not a suspicious activity," and threatening to arrest people for photographing police chills free speech. The letter went on to say that, "This activity is protected by the First Amendment and may not be restricted by officers wishing to avoid the documentation of their actions. This is just the most recent incident in a rash of similar police abuses across the country."

The Sun and the NPPA's letter noted that police have found a loophole that allows them to arrest people not for taking photos per se, but rather for loitering.

This latest incident follows the Jan. 29 arrest of a TV photojournalist in Memphis who was detained, and had his photos erased, after he used his cell phone to record police making an arrest.

With a growing number of journalists and citizens being arrested for taking photos or videos -- the arrests of reporters and photographers covering the Occupy protests resulted in the U.S. dropping 27 spots to no. 47 on Reporters Without Borders' 2011-2012 Press Freedom Index -- Poynter has published advice for "how journalists can protect themselves and the news they’ve gathered if arrested on the job."