Where do I look?

[WendyPusey]

I have just been given a tree of my OH's Pusey family. It says that his 3 X Great Grandfather Nathaniel Pusey was jailed for 1 year with hard labour for poaching, in 1820 Taplow.

I've never had to look for any criminal records etc before so can someone give me some advice as to how I can find some information to verify this please.

Can't ask the person who drew up the tree as they have passed on.