Am interested in becoming a counsellor to help my fellow police officers.of late there has been killing?

Am interested in becoming a counsellor to help my fellow police officers.of late there has been killing by police officers. killing other people their bosses and killing themselves.this has made me to get interested in getting the solution to this bad things that are happening to my police department. i have undertaken a diploma course in counselling psychology on a scholarship bases. am happy that something is coming out of my training.how do i become an expert in police psychologist?