The first ACT parliament overflowed with political parties - five among the 17 members. The third held two independents; the fourth parliament had three. But for 18 years, the chamber has been bereft of independents and has become a stronghold of the major parties. Worse, for all of those 18 years, there has been one party in power. The well-documented consequences of that include an unhealthy cross-pollination of Labor staffers and public servants, and the dangerously interdependent relationships between the people who hold the political power and those who hold commercial power. Democracy thrives on cleansing elections.

That 30 years of self-government has brought us to this is an indictment on both major parties. One of the reasons for the concentration of power in Labor is the increasingly less proportional voting system. While independents have been elected across the city in previous Assemblies, the seven-member electorate provided the most fertile ground for people trying to get elected without the backing of a major party. That electorate was abolished at the last election, leaving the maths working strongly against independents and minor parties.

The Greens were the lone voice among the political parties calling for a more proportional voting system, but Labor and Liberal ganged up to push through five-member electorates across the city. The result in 2016 was Labor won 38 per cent of the votes and 48 per cent of the seats; the Liberals won 37 per cent of the votes and 44 per cent of the seats. Minors and independents (Greens excluded) won 14 per cent of the votes and no seats.

Thus it will remain until the Liberals finally face the reality that has been glaring at them for 18 years and more: Bar a minor miracle, they will not win majority government in Canberra, and if they want to pry Labor's fingers from the levers of power, they must embrace independents, minor parties and a much more messy, enlivening and democratic Assembly. The system we have guarantees the two big parties 10 seats each of the 25 seats as a starting point. To win majority government, the Liberals must win a third seat in Tuggeranong, and in Gungahlin and Molonglo. They believe it possible; history and the bare and present facts say otherwise.

Seven-member electorates were favoured by the last electoral commissioner, Phil Green, for the very reason they are more proportional - and therefore the number of seats won by each party is more closely aligned to the vote. With the Greens support, the Liberals could legislate for, say, two nine-member seats and one of seven. This was the model pushed at the last election by the Proportional Representation Society, which pointed out that in a five-member electorate, candidates need 16.7 per cent of the vote (with preferences) to get elected, prohibitive for all but the best-known independents. That drops to 12.5 per cent in a seven-member electorate and 10 per cent in a nine-member electorate.

Ten per cent is too high to see strays and randoms padding the corridors of power, if that is your fear, but it is achievable for independents with solid support who are willing to put in some hard work to get there.

With self-government cemented over 30 years, the challenge is to shake up the voting system and deliver real power to Canberrans.