Guardian: Barack Obama's authority to compel power plants in the US midwest to reduce the smog and soot that blow across to north-eastern states will be put to the test on Tuesday in the first of three major challenges to environmental regulations.
The supreme court will hear arguments about whether the Environmental Protection Agency (EPA) can set limits on air pollution that, while originating in one state, directly affect the air quality in other states.
It is the first of two cases this session that...