While playing I was a bit confused, because the description said to interact with suspicious areas, but the entire city looks quite normal, not like a crime scene. So I just walked around the city pressing E until I found a clue. I thought I had to find more than one clue so I continued walking around the city looking for more until the time was about to run out. I then went to the police station, made my accusation and won.
I liked the idea, but I think having visuals that give a clue about where to look, having multiple hints that have to be pieced together, and having hints pointing to the next point of interest would elevate the experience.
That said, I understand that you had limited time and the experience was quite fun.