How Trump's census question could transform America's electoral map

If the Trump administration adds a new question to the 2020 census, up to 4m people could go uncounted, paving the way for Republican gerrymandering

It has happened every decade since the foundation of the United States, mandated by the first article of the constitution. It is a centrepiece of American democracy, playing a vital role for political representation in Washington. And its viability has never been under greater threat.

The United States census, the measure of America’s population growth and its distribution – irrespective of immigration status – is...