So, you catch a 'thief'...

he did say he lost his key somewhere....
maybe it happened the day before......
so he brought his helmet into work with his hacksaw and pliers so he could ride home again after freeing his bike up?

just because he looks like an Irish gypsy doesn't make him a thief ;)

if he is a thief, he's a helmet-wearing thief, which for some reason is hilarious to me.

'keys, wallet, boltcutters, hacksaw, knife, lights, hi-viz.......helmet!'

Valid point but that's the grey area. He may well have been genuine and gone back to work to fetch a set of plyers and hacksaw but I find it hard to believe that these sort of items are 'just kept at work'(unless a builder/chippy/sparky etc).
Also, as mentioned, I don't know cyclists that carry a 9/10inch set of plyers and 10/12inch hacksaw in their bag