Wrong righteous defense, uses melee hit rating.
Thats how pally itemization fail again and again, a pally have all stats involved, int str, melee hit (arguingly spell hit its pretty useless except exorcism and first tick of consecration but still they put it on our gear).
Or Im just wrong and stupid and this isnot supposed to be a pally shield, but a shaman shield...

I hope Blizzard dont expect to make us think its a pally shield.

More probable, the items desiners dont even know how the pally protection work, and they thought we were using spell hit for everything instead of melee hit (which is a comon mistake everybody does at least once)...
Or its a hybrid stupid shield, they wanted to give shaman and pally protect a shield, so they put +block rating +dmg +hit rating

give me a break...geez

still I wont use that shield for bossess, but it could be nice for aoe, or trash mobs with a spike