When the Brotherhood, Mafia or Cults are involved is chaos inevitable?

When people met the brotherhood, mafia associates and or cults then chaos follows and circumstances are dier, what can be investigated. Who can you go to when thing go wrong? Not the police! Even thought the wife was poisoned and the sister died, both of which where to divorce soon, neither had support systems and were isolated from family. Niether were blood related. The wife's gard dog was hurt around the same time then put to sleep.