Should the United States government be able to conduct a search of your emails if they are stored on a server in another country, or does the government’s right to examine digital evidence stop at the border?

That is a central question in United States v. Microsoft, a case scheduled to be argued on Tuesday before the Supreme Court.

Both sides in the case have legitimate concerns. If the court sides with Microsoft and declines to allow searches for data stored in another country, the government will be hampered in investigating crimes like terrorism, child pornography and fraud.

If the court sides with the government and rules that it may demand data stored overseas by American companies, those companies will find it much harder to do business abroad. This is because many foreigners fear that United States warrants authorizing such searches will disregard privacy protections afforded by their country. The government of Germany, a country with stringent privacy laws, has already indicated it will not use any American company for its data services if the court decides to allow searches.