Consensus democracy is the application of consensus decision making to the process of legislation. It is a narrow, but perhaps the most important, application of consensus decision making methods. There is no form of government that applies consensus so uniformly, however, the most liberal forms of Islam as a political movement do hold this up as the ideal theory of civics (see ijma for the details.).
The term deliberative democracy is also often used to emphasize opportunities for deeper debate on issues of bodily importance to the community (bodies being the concern of politics as such). It is to be differentiated from consensus models since it focuses on discussions, not decisions.
The term grassroots democracy is somewhat looser and is often used to imply a broad range of consensus-promoting measures, short of a full consensus democracy. This term is generally preferred by those who are not claiming to promise a "strict consensus" system (which is interpreted by many as meaning "act only on unanimity"), e.g. if there is to be an integration with an existing representative democracy.
In general, the term 'consensus democracy' is usually associated with the political 'left' while the term 'semi-direct democracy' is usually associated with the political 'right'. The term 'grassroots democracy' is more neutral and has been employed by both 'the left' and 'the right' in the English-speaking world and its institutions. For instance, the Green Party of the United States, the United States Republican Party, the Canadian Alliance, and the Green Party of Canada have all used it in the recent past. There seems to be consensus on the term 'grassroots', even if there is often little similarity in the measures proposed.
Nonetheless, there remain people who believe that pure consensus decision making can be applied directly to make major political decisions, so the theory of consensus democracy remains distinct.
Requirements to put this theory into effect are
- a clear definition of the degree to which people are answerable to non-human power (in Islam this is the khalifa)
- a clear definition of the people affected and thus involved (in Islam these are the umma)
- a clear definition of the degree of effort and expectations of patience required for the solution (in Islam this is ijtihad)
- a discipline among the learned (in Islam, the ulema or scholars or jurists) to teach and apply this method to reach rulings in the law (in Islam, the sharia), and to avoid precedent overwhelming the current reality of circumstance (in Islam this often did occur, is called taqlid or "blind imitation", and led to the freezing of the classical fiqh under the Ottomans)
- a willingness to adapt to local customs and usage, where these represent constraints (in Islam this is the al-urf or "the custom")