well, if the "somebody" is a large organization with tons of times and money to pay the lawyers, they might consider taking out private prosecution, right. But then, any large organization with tons of money would prefer to stay pals with the government, for obvious reasons, and private prosecution, you know, just informal advice, nothing official, you know, will not go down well in the broad context of your organization's activity in the UK...
as to an individual... sigh.