ALL PHOTOGRAPERS SHOULD KNOW THEIR RIGHTS!
The only reason we know about the police murder of Walter Scott is the courage of a bystander who videoed the events on a cell phone. That man had the courage and wisdom to give the video not only to the police but to the press. Those rights are protected by the first amendment.
The courageous citizen was afraid that the police on the scene might have confiscated his phone. He had reason to fear. During the news tonight about North Charleston, a family member of the murdered citizen described how he had gone to the crime scene during the investigation. The family member used his cell hone to take pictures of the police procedures. That phone was illegally confiscated by the North Charleston police.
I have had police officers try to take my camera as well. I have also had them tell me I am not allowed to take pictures. Neither claim is correct. As long as you are in a public place, you are free to photograph. The only exception I believe may be true is certain federal operations, including TSA security lines. Even there, the police NEVER have the right to confiscate a camera (or a phone) without a warrant.
I always recite my rights under the First Amendment and, if I expect to be detained, I carry a piece of paper like this with a statement of the law.
Unless they have a warrant or some urgent reason to believe you have committed a crime, no police office has the right to confiscate your camera and certainly they have no right to confiscate your cell phone.