Not so simple
The House of Lords ratifies any bills and laws passed by the House of Commons.
They have sanity checked and rejected an awful lot of the more controversial crap being pushed through.
I don't like the idea that the position of being a lord is hereditary, but I do like the idea that they aren't part of the same system that creates the members of the commons. Making it very difficult for the Murdock empire to have it all thier way.