Astonishing but true that even the plain right to photograph a train requires a defense:
Mr. Daniel Dedinas, a railfan whose hobbies include photographing trains, was near the train tracks behind the FedEx store on Newark-Elkton Road, waiting to photograph the unique locomotive as it passed through Newark. He was stopped by two Newark police officers, who acknowledged that they had no probable cause to believe he was committing or about to commit a crime. Mr. Dedinas gave the officers his name and address, but standing on his right of privacy, he refused to give the police his drivers license or other identification. In response, the police told him he could not photograph the train until they confirmed his identity. Before that was accomplished, the locomotive passed by.
The First Amendment protects peoples right to take photographs of activities taking place in public, including passing trains. Further, Delawares laws grant police the authority to demand identification, but only when there is reasonable ground to believe that the person has committed, is committing, or is about to commit a crime. Newark police have now been instructed that taking pictures of trains and railroad equipment is not grounds for stopping individuals.
After ACLU-DE intervened, the City of Newark and the Newark police acted quickly to retrain officers on stop and identify laws, thereby protecting the First Amendment rights of other railroad photographers and members of the general public. Mr. Dedinas also received a letter from Newark confirming his right to photograph trains.
Via Train Photography: A Protected Free Speech Right | American Civil Liberties Union.