Black Community Lynches Equality

Prop 2 here in Florida was going to pass no matter what.

However, new numbers in California show that Prop 8 passed with the aide of higher black turnout:

A few people seem to be interested in whether or not the black vote was decisive.

If the following standard analysis assumptions are true the answer is probably a very close ‘no’, but at least one of the assumptions seems very possibly false and with other fairly likely assumptions the answer looks like a ‘yes’.

My assumptions are:

1. that the vote among black people was as reported (69% Yes on 8).

2. that black people make up 6.7% of the CA population

3. that black people represented a share of the votes equal to their share of the population

I further assume that 8 passes with 52% which seems the likely number at this point.

Given each 1000 voters, black people in CA represent 67 of them.

There are 520 Yes votes and 480 No votes for each 1000.

At 69%, Black voters voted 46 Yes and 21 No for each 1000.

If they voted like White voters (55% No) they would have voted 31 Yes votes and 36 No votes.

That would make the final tally 505 Yes and 495 No votes. (50.5% to 49.5%). [numbers very slightly rounded]

But this analysis is VERY sensitive to assumption #3. It appears that black people in CA may have voted in a greater share than that of their representation of the population. Right around 10% of the vote.

That would mean that given each 1000 voters black people in CA represent 100 of them.

At 69% Yes on 8 that would be 69 Yes and 31 No for each 1000. If they had voted like White voters they would have voted 45 Yes and 55 No. That would make the final vote equal 496 Yes and 504 No (proposition loses 49.6% to 50.4%).

Interestingly, at the 10% vote share level, if a small majority of black people voted against the measure it would have lost (49% Yes, 51% No gives the measure a loss at 49.9%).

Basically, if the black voter share is 10% or higher, the black vote difference from the white vote made the difference so long as the final total is at or below 52%. And if the black voter share is any higher than 10%, it made the difference even if black voters had only split 50-50 instead of the 45-55 shown in white voters.