He's being harassed by a law firm, not the mob. If someone shows up to do him harm they will be from the government because the law firm will have contrived government process to that end.
Shooting at them while they're on the clock is generally not wise.
It's not that far fetched to assume that someone could be in physical danger after ruffling the feathers of a company that has hired a union busting firm. Union Busters have a long history of employing gun violence against striking workers.
I would agree. The history of union busting is full of examples a violence by the union busters via private contracts and government agencies. There are probably more violent, than non-violent examples.
The Pinkerton Agency is basically a murder-for-hire company, historically. They generally only cater to corporate customers, so politicians kept their eyes turned elsewhere.
Shooting at them while they're on the clock is generally not wise.