Confessions of a Madman

Confessions of a Madman is a cosy mystery/crime series of four books, literally about confessions of a mad man, or is he really mad? Maybe his confession is true and some strange crime is happening. These books are available as a box set and individually. You need to read all four to complete the story.
Amanda and Jade, two policewomen who work in different towns, but who have been friends for years, meet for a friendly chat. By chance they each tell a story of a strange confession they had to listen to. Both unbelievable confessions are just about identical. This immediately makes one thing obvious to them - there has to be a criminal somewhere doing something no one had ever heard of before. The two confessions are too alike for it to be a coincidence.
Their first problem is to prove these two incidents were committed by the same person while showing beyond doubt it isn't some sort of elaborate hoax.
As the story follows the investigation, the women hear more about some of these 'mad confessions' and go on the trail of the man responsible. Eventually all the pieces start to fall into place, but there is one thing they can't get a handle on, no matter which way they look at it. That is how the criminal chose his victims.
Book 2 sees Amanda and Jade interrogating one of the so-called mad-men, who seems to be quite sane, providing he is telling the truth. The two officers believe he is.
There is also some turmoil and upset in the station, but as that gets sorted, so a call comes that is the one they have been waiting for. They rush off to speak to yet another man who wants to confess to the same thing. This time he isn't thought to be insane.