Why does Bruce Cable hire a private firm to investigate the death of his friend, Nelson Kerr?

Bruce Cable hires a private firm to investigate the death of his friend, Nelson Kerr, whois killed during a hurricane. With state and local police stalling and a good deal of evidence washed away in the storm, Bruce hires theprivate firm to help him sort out how Nelson’s latest novel, a book about a questionable drug and Medicare fraud in nursing homes, may have contributed to his murder.