Let us be specific here.
The 'Police' have not shared information, individuals have taken the decision, authorised access to the data and instructed their subordinates to comply.
Providing personal, damaging data to a non statutory organisation is illegal and the individuals concerned should be punished by law.
In effect, it is the same offence as a member of the Police providing information to a newspaper or a criminal organisation.
They should NOT have the option of retiring to full pension on 'ill health grounds' as soon as a sniff of an investigation heads their way.
They should be punished as you or I would be - irrespective of their motivation (for the 'greater good'), rank, or subsequent results of such a leak of information.
The law is the law, and applies equally to all.