Can I reveal the names of the guilty when writing if the info can be proven? ?

I have been procrastinating writing a book that has been burning in my heart for many years. I am not sure where to start .. It is overwhelming to think about. It is about my father who was poisoned by arsenic. and my 25 year fight with county officials to reveal this truth .They fought me on this because I made known to them that I highly suspected others died of poisoning before my father. meaning other victims would also need to be exhumed for autopsy. if I was correct about my father. They fought my fathers exhumation for 20 years and when I was finally able to exhume for an autopsy the county disgarded the toxocology results because they did not want to be guilty of neglect and I I believe at least one other has died since and maybe even more. I have a need to write but don't know where to start. This story has been reported in the news but denyed by the county officials . It burns within me. If what I speak is true and can be proven , Can I reveal the names of the guilty , those who committed the crime and those who concealed it?