/ //Mathematics has helped a US court to overrule an example of partisan gerrymandering in North Carolina.Credit: Jonathan Drake/REUTERS// // //Mathematicians are no longer devices for turning coffee into theorems, as the Hungarian mathematics researcher (and caffeine addict) Alfréd Rényi is said to have claimed. They seem pretty useful for preserving democracy, too. In striking down the way that officials in North Carolina unfairly partitioned the state into electoral districts, a US federal court last week conspicuously cited the work of mathematicians including Jonathan Mattingly, an expert in mathematical modelling.// // //In a 200-page decision released on 9 January, the three-judge court in Richmond, Virginia, said that the districting had unfairly favoured the Republican Party. Maths played a key part in helping the court to reach that decision, by demonstrating the unlawful use of partisan gerrymandering — fiddling with district boundaries to include or exclude certain voters and steer the results of an election. Those apportioning districts might draw borders that pack large numbers of voters for an opposition party into a small number of districts, for example, limiting the number of seats that the opposition can win. The process has been likened to allowing lawmakers to choose their voters, rather than the other way around/. https://www.nature.com/articles/d41586-018-00661-x?utm_source=briefing&utm_medium=email&utm_campaign=20180118 Of course there are other ways to improve the process besides drawing the district lines so the elected officers more nearly match the electorate preferences, e.g. instant run-off, multiple seat districts,... Brent