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Parliament

Capitalize with name of nation:
            Italian Parliament

Always capitalize in reference to British Parliament, even when standing alone:
Parliament
Mother of Parliament
Houses of Parliament

member of Parliament
the House of Lords
House of Commons
parliamentary
the Lords
the Commons
Generally use the proper name for the legislative body of a country:
            Israel's Knesset
            Japan's Diet
            Germany's Bundestag

For general reference parliament or legislature may be used:
            The issue has surfaced in the Diet, Japan's parliament.