The town has a history of crime from its earliest begininngs.
Highwaymen mostly, much of that same energy remains in the present.
Dont carry valuables or use the multi storey car parks, dont bring your wife or kids !
In fact avoid the place like the plague, it sucks and many locals want to leave.
It always strikes me that quite a few of the shops that officially close at 5:30pm start putting their shutters down before 5:25pm, stop people going in before 5:30 & in some cases (the branch of a national chemist chain that sounds like a kind of footwear) refuses to serve people already in the shop circa 5:28pm.
This creates a "couldn't care less" image where the staff, management, or a combination of the two put 'knocking off' as soon as possible above service and 'going the extra mile' for customers, including people who might spend more than the average punter.
WHS & Sainsbury's stay open longer & are, in my considerable experience of Princess Square, two of the better firms there. They also stock a number of items sold by the shops where the staff & management can't wait to clear off.
I have been strongly advised never to go to The Bull in the evenings as it is supposed to be the roughest pub around, so just you be careful if you decide to go. Trouble apparently happens between regulars and other young people, just don't be hanging around there in the evenings if you don't want anything to do with it.