[EM] Looking for a paper on Plurality Block Voting and US municipal elections that was noted on this list a while back

[Scott Ritchie]

A while back someone posted a paper to this list talking about different
voting systems used in local government in the US. Particularly
memorable to me was that plurality block voting is still the most
popular for city council elections (ahead of districted plurality),
despite being at one point declared unconstitutional by the Supreme Court.

Does anyone remember where this paper is?  Or at least what the court
case was?

Thanks,
Scott Ritchie