An afternoon in Lisbon

Today I was taking some shots in a public garden. I pointed my camera to a place were 2 adults and children were playing. 150 feet away. Suddenly a female does shout : " No pictures of children ". I said nothing. She insisted : " Are you taking pictures of children !? No pictures of children !!!". I had actually taken no shots. She was too far away. 2 minutes later she ,the children , and another individual left. I thought the whole episode was over..., but it was not. Suddenly when I was returning home a car stopped near me . It was the woman again !!! " You must not take pictures of children !! You must delete them from your camera !!". I did continue walking. The car did follow me for a couple of feet and it did stop again. A woman did jump out of the car and did confront me : " Delete the pictures from your camera !! You must delete the pictures !!". I did reply something to her but I realized it was uselless to argue with her. I told her that and did continue walking. A few feet away there were 3 cops waiting for me and a police car. They asked if I were taking pictures. I told them the story and they asked me for the camera. I did show them the camera. They did browse the pictures..,there were no children pictures. Cops told me that , according to the law , I could not take pictures of people in public places , in particular children. Portugal was rocked by a paedo scandal. A few years ago it was discovered that in a state run institution for poor children there were paedophiles. Cops went away and later I read what law says. In portugal it is legal landmarks , streets etc . No problem if such pictures show people.
But if the main subject is a child or adult , such person must give his consent. Cops do interpret the law with " no pictures of people ".
No shots in public gardens were children play.., schoolyards.., etc.
Media can publish such pictures tought. When there is what might be considered an event journalists can take pictures.
I do not criticize the police. I criticize the law that does say that an amateur photographer cannot take pictures of people without their consen , even when they are in a public area.
Street photography with such laws is impossible.