Practically, the UK Monarch (or Japanese emperor) has no discretionary political power at all. Republican Parliamentary systems usually leave some discretionary

Practically, the UK Monarch (or Japanese emperor) has no discretionary political power at all. Republican Parliamentary systems usually leave some discretionary power to the head of state in either emergencies or for the purpose choosing a party to attempt to form a government. Hereditary Lords (i.e. the noble aristocracy in the UK) have almost no political power. The ninety or so still in the House of Lords are elected by fellow members of the House of Lords. The remainder (600+) of the peers are appointed by the party in power in the commons.