One glaring example is over the number of chief executive candidates. The options are: two to four, eight at most, and 10 or more. But this is a sham. The real question is whether there should be a procedure whereby unwelcome candidates can be excluded. The way the options are put, chances are most people will choose 'two to four' as the most reasonable answer. This means a mechanism will be required for the nomination committee to pick the right number of candidates out of however many. Almost any system of selection will succeed in excluding a democratic candidate such as Alan Leong Kah-kit. The system may well produce two candidates, both of whom are Beijing favourites.

To expose the traps and, at the same time, encourage the public to respond to the green paper intelligently, the democrats have launched a 'recommended response' street campaign this week.

However, this is not enough. To stall, mislead and sap the energy of the democrats is only a small part of the green paper's game plan. The more serious aim is to change the goal radically, once and for all, by redefining 'universal suffrage'.

In a way, Mr Tsang was not lying when he promised an 'ultimate' solution to the issue of universal suffrage, and said that how soon universal suffrage could be achieved would depend on the model chosen.

If election of the chief executive by 'universal suffrage' means forming a strictly conservative nomination committee which can, by its nomination procedure, exclude all but two or three candidates, all of whom have the central government's prior approval - then Beijing will probably be more willing to agree to 'universal suffrage' sooner.

Likewise, for the election of all members of the Legislative Council by 'universal suffrage', it could mean just replacing the functional constituency seats with indirectly elected district councillors, or even retaining these constituencies, but allowing the general public to vote after the candidates have been picked by business and professional groups.

Is either of the above models consistent with what is generally understood by the term 'universal suffrage'? Both models are 'options' in the green paper. Chapter Six, at the very end of the green paper, gives the game away. It contains the models mentioned previously for the 'universal suffrage' election of the chief executive, and all of Legco.

Another paragraph says it all: 'We are all committed to 'universal suffrage', but the 'universal suffrage' the government is committed to is as defined by the Basic Law, not as defined by the international standard of Article 25 of the [International Covenant on Civil and Political Rights]. It is a kind of 'universal suffrage with Hong Kong characteristics' designed to preserve prosperity and stability, to facilitate the 'capitalist economy', to reflect the proper relationship with the Central People's Government and the 'executive-led' government.'

The lie is in cheating Hong Kong people and the world with a fake copy of democracy. This is what the ultimate stakes are. Are we going to let Mr Tsang get away with it?

Once established here, 'universal suffrage' and democracy will be defined in the same way and on a permanent basis for the rest of China. This is what the democrats in Hong Kong have to fight for; the line that Hong Kong will have to hold.

The green paper is an attempt to cheat by confusing the public with complicated details. Universal suffrage is not a question of quibbling over definitions. It is simply the basic requirement for fairness: a fair system of government, of exercise of power; a fair system for solving problems to reach fair policies, to give the people a fair deal. In the public debate on the green paper, we must never lose sight of this.

Margaret Ng Ngoi-yee is a legislator representing the legal profession and a founding member of the Civic Party