I get, "No results found for "probation officer attacked"."
Of the first page (after removing quotes) it only appears that there's one story about someone actually attacking a probation officer. But there is this nugget: Probation officer stabbed neighbour with garden fork at bonfire
Note, if you search for "social worker attacked" (with quotes removed) you get two stories on the first page about social workers being attacked.
So clearly being a social worker is twice as dangerous as being a probation officer. And they're far less likely to attack people with forks.
My guess is localization is tweaking your results.
Anyway, here is data. Law enforcement (which includes parole officers) and bartending have the highest rates of workplace violence, social workers aren't on the list.
