In my post of yesterday, I asserted that for a Liberal Democratic Party-sponsored no confidence motion to pass, LDP president Tanigaki Sadakazu would have to round up every member of every one of the opposition parties, all of the independents and then 17 members of the Democratic Party of Japan.
Alert reader RK asked in an email: "Are you sure 17 is the correct number?"
Interestingly, the news media in recent days have not posted any hard numbers on exactly the number of ruling coalition defectors the passage of a no-confidence motion would require.
The number, however, is certainly not 17, save under a special case of a specific number of Representatives abstaining.
There are 480 seats in the House of Representatives. At present one of these seats is empty, meaning their are 479 representatives. Furthermore, the Speaker of the House, former DPJ member Yokomichi Takahiro, does not vote, except in the case of a tie.
So the number of voting members will be 478. Half of that number is 239. For the motion to pass with all members voting, those in favor must number 240 (50%+1).
The ruling coalition is composed of 250 member of the DPJ and 4 members of the People's New Party. With 254 in the ruling coalition, Tanigaki would have to lure 16 of the ruling coalition (254-16 = 238) into voting for the no-confidence motion.
However, the chance that everyone will be present and voting is unlikely. The Communists (9 votes) will likely abstain, as they are wont to do (Then why are they even in the Diet at all? Heck, I do not know). This would raise the bar to 20 defectors (469/2 = 234.5, 50%+1 = 235, 254-20 = 234).
Of course, members of the ruling coalition could abstain, lowering the number of defectors needed. Indeed if all 17 of the DPJ Representatives currently under suspension for having voted against the legislation raising the consumption tax abstained, and all the members of the opposition voted for the no-confidence measures, supporters would only have to lure 6 members of the DPJ to switch sides, (478-17 = 461, 461/2 = 230.5, 50%+1 = 231, # in the opposition + independents = 225).
As the math indicates, however, a significant slice of DPJ legislators would have to be sending clear signals on their giving up on the party and the LDP would have to be exercising strict discipline over membership of the rest of the House before Tanigaki could entertain a hope that a no-confidence motion could pass.
The LDP, a cautious, even timid organization, does not move on hope alone.
So the while the idealized minimal number of defectors is 16, the actual minimum is fluid, and the ability to round up the correct combination of defectors and abstainers ostensibly beyond the capacity of the current opposition.