I thought this sort of behaviour was limited to the deepest, darkest South West!

[Ghost]

BBC News - Birmingham father and daughter sentenced for incest

 

[Seadog]

...pleaded guilty in July to having sex with a relative

Since when was that an offence? Banging the wrong kind of relative will land you in jail and a lifetime of being subject to the mocking opening bar of Dueling Banjoes but wives and husbands are not off limits. Nor are cousins although first cousins making babies it isn't very wise.