Writing for Aeon, David V. Johnson says a legislature should be "large enough to reflect the interests of an entire people." He notes that James Madison, the architect of the U.S. Constitution, sought to grow the House of Representatives as the population grew.
"James Madison, that genius of representative institution-building who, along with America’s founding fathers, set an original benchmark of one representative per 30,000 citizens. Anticipating an ever-growing country, he proposed an amendment be added to the Constitution that would increase the size of the House according to population, with the ratio changing slightly with an increasingly large house: once the House had 100 members, the standard would be one representative per 40,000; 200 members, one representative per 50,000. But the amendment failed."
"A more realistic standard perhaps is the current global norm for representative democracies: approximately one representative per 146,000 people. Of course, many democratic countries are quite small, but even large countries such as Germany, France and the United Kingdom manage to hit this target by having rather large lower houses, with 630 seats in the Bundestag, 577 in the Assemblée nationale and 650 in the House of Commons.
"The US and the EU are at the less representative end of the spectrum. The US’s lower house has one representative per 744,000, and the EU, whose parliament has more limited powers (eg, it cannot introduce legislation) has one per 677,000 citizens."
Nathan Pippenger riffs on this subject for Democracy journal. Speaking of the growing citizens to representative ratio, Pippenger states, "high ratios do cut down on the time and resources that representatives have for each constituent, or the likelihood that they’ll have enough in common to understand each other."
Each article takes the view that the nexus between citizen and legislation would be improved through an increase in membership. Neither, however, grapples with the intra-institutional effects of increased membership. Would more members make for less law-making? Would it empower additional oversight? questions like these are worth analyzing.
Read more at:
David V. Johnson, "A Democracy Deficit Plagues the US and the European Union," Aeon, August 2016, https://aeon.co/ideas/one-way-the-us-and-the-eu-are-less-democratic-than-china; and
Nathan Pippenger, "Fuller House: Would Larger Parliamentary Bodies Help Solve the Problems Facing Modern Democracies?" Democracy, August 4, 2016, http://democracyjournal.org/alcove/fuller-house/.