crime and justice reporter joy lepola uncovers what you did not see and why. >> police at preakness, making an arrest, concerned with cameras. what they were capturing. >> she did not appear to be a threat to anybody. >> mary pat bizzell was in the crowd. >> within a couple of minutes, the girl was laying on the ground in a puddle of blood with a police officer on top of her dreaming at her. and people trying to take videos. >> bizzell saw what was happening with cell phones. >> one of the gentlemen next to one of the friends. camera taken, and pictures erased. >> it is wrong, illegal and ii should stop. >> police say it never happened. >> we're focused on violent offenders not people with video cameras. >> if then, the baltimore city police departmenttargues they could. >> if you are recording a video, or device, which includes audio, you are breakinggthe state law. state law indicates that you cannot do that. and we can seize that device and effectuate an arrest because of it. >> they have no right to do that. that's an illegal search. and it is an illegal seizure. >> by law you ca