Trump’s threat to appoint a special prosecutor is something he can do but should not do.

At the second presidential debate on Saturday night, Donald Trump threatened that if he became president, he would instruct his Attorney General to appoint a special prosecutor to investigate Hillary Clinton. But could Trump actually do this? Katy Harriger reviews the recent history of special prosecutors and the presidency, and writes that while Trump certainly has the ability to do so, the checks and balances of the legal system would likely limit the extent to which Clinton could be pursued. She comments that Trump’s desire to use his executive control over law enforcement to punish political rivals smacks of authoritarianism and could be very damaging for the country.