World's most demented electoral system?

[ag]

The Turkish 10 % PR threshold and its consequences are pretty undemocratic and stupid, but you can cleraly understand the political interest behind it so I guess it's not "demented" per se.

Nor is the Chilean binomial, in that sense. Both a wrong from the standpoint of the society at large, but both perform admirably the job they have been invented for.

[ag]

Mexican Electoral system in the 19th century (even for the brief periods where it was neither a dictatorship, nor at war). It was, actually, not particularly peculiar at the time, but I simply know Mexican case better.

Each state was divided into districts, which where in turn divided into the subdistricts of equal size. Citizens voted for electors representing a subdistrict. The electors would gather at district headquarters and vote for whomever they were supposed to vote for (President, Supreme Court President, who doubled-up as VP, their own Congressmen, governors, state legislators, etc.). In practice there would typically be disagreements on where the electors were supposed to gather and who was an elector, so multiple returns would be submitted - it was a glorious mess. 

[ag]

Soviet Congress of People´s Deputies.

This was a monstrositiy of 2250 deputies that Gorbachev somehow thought of as a "democratization" device. Up until then the Soviet system had evolutioned into something resembling a two-chamber legislature (Supreme Soviet), albeit only notionally "elected." The upper house (Soviet of Nationalities) was a bit like US Senate (representing oficial ethnic groups, based on administrative divisions) and the lower house (Soviet of the Union) was theoretically based on equal-sized districts. There was also a standing Presidium of the Supreme Soviet, which somehow was a collective head of state - but the rest of the architecture was fairly unimaginative. Gorbachev, when thinking how to admit a bit of democracy, let his imagination run.

So, the new Congress of People´s Deputies expanded both old chambers and put them together into a joint legislature of 2250 members. Of these

750 were elected in single-member constituencies of equal size into which the whole USSR was divided
750 were elected in the old "nationalities" fashion: still by single-member districts, but not on equal population basis: 15 per Union Republic, 11 per Autonomous Republic, smaller allocation for the lesser autonomous ethnic units. Entire City of Moscow was one district for these purposes, as it was, roughly, 1/15th of the Russian SFSR.
750 were chosen by "social organizations": 100 from the Communist Party, 20 (?) from the academy of Sciences, 1, if my memory serves me right, from the Society of Philatelists.

All these people, from Yeltsin (elected in the gigantic all-Moscow district, getting 90% of the vote against the Gorbachev-supported director of the largest car factory in the city) to the philatelist (who, probably, appointed himself) set in a single chamber. And that chamber had to elect the day-to-day two-chamber legislature (technically still called the Supreme Soviet) from among its members.

It was horrid, but it was quite fun It was the very first time we actually had some real elections, at least in some districts. Even though the government, locally, still fully controlled ballot access, being allowed to strike candidates of at will, in some places it still allowed real competition (Moscow being one such place).  And campaigning was quite lively. At least in Moscow, Leningrad and the Baltics, pro-government candidates lost in huge landslides. And Academy of Sciences chose Sakharov.

[ag]

Made me think of the past Yeltsin, who had been fired from all his posts, including the Moscow Communist Party leadership (de facto mayoralty) chose to run in the gigantic City of Moscow "national-territorial" (shoot, I still remember the word!) district No.1. The government could have struck him off - but Gorbachev, after some doubts, thought he would manage this (hoping to expose Yelstin as only having limited popularity among the content Muscovites). To compete with Yeltsin they chose Brakov, the head of the largest factory in the city. Just in case, they had all the Army units, stationed in Europe and all other Soviet oficials and workers abroad (embassies, foreign aid missions, etc.) vote  in that same district.  I remember the ditty: "From Tokyo to Krakow - all to save Brakov". Yeltsin romped home: 90%+ of the vote. I think that must have been the moment Gorbachev first started understanding how unpopular he himself were.