Taking photos in public places is not a crime
This is the lesson that law enforcement learned from the Rodney King episode: Attack those who would hold you accountable for complying with the law you are sworn to uphold.
Police fear video cameras because they cannot be impugned.
Normally cops are able to get away with murder, sometimes quite literally. They can conspire to lie and make up pretty much any story they like as long as it is even marginally consistent with the known facts of the case. When push comes to shove it is the word of several police officers against someone accused of a crime. Who are the judge, the jury and the public, going to believe?
But when those cops are videotaped, their ability to spin-doctor what happened in order to bury the accused and/or cover up their own wrongdoing is extremely limited.
They especially fear being taped without their knowledge and having that evidence show up AFTER they've perjured themselves or filed false reports.
It is for this very reason that the right to videotape police conduct, especially surreptitiously, should be protected by law. It is at least as fundamental a right as free speech or the right to keep and bear arms. When agents of the state are empowered to detain and incarcerate private citizens for violations of the law, those citizens have the right to an impartial observer to ensure that those agents are conducting themselves in accordance with the law and with respect for the truth.
There was another case not too long ago where a teenage hoodlum used an MP3 device to record his own interrogation at the hands of the police. One of the cops he dealt with later lied on the stand about what took place during that interrogation, only to be destroyed by the truth.
Now the teen in question was a criminal. He was guilty of the charge, but because the police lied those charges were thrown out. Furthermore the police who perjured themselves destroyed their careers and opened themselves up to criminal charges of their own.
A good cop who does his job honestly and tells the truth has nothing to fear from the truth. Only dirty cops who look to shortcut the due process of the accused, or who are criminals in their own right, fear having their official actions recorded.