Movies, television, internet and other forms of media are the most common source of information regarding the Yakuzas. Getting first hand information can be dangerous and might get you involved somehow. However, photographer Anton Kusters took it further and documented the gang for quite some time. Here’s a tidbit of what he has to say about the experience.
I was extremely nervous. Since they are gangsters, I thought I should be very careful, in case I shot something I wasn’t supposed to see. But this actually upset the gang. They saw my nervousness as disrespectful. I remember one time early on this guy pulled me aside and said, “You are here to take pictures. Act like a professional.” It turned out they respected me if I was really aggressive about getting a certain shot. To not take photos was a sign of weakness.
Read on the source link to know more about how he did as a photographer for the Yakuza.