(Chip Somodevilla/GETTY IMAGES)

The legal documents are complicated — one suit, from Notre Dame, comes in at 57 pages. But the thing to know is this: Everything hinges on how courts interpret a law called the Religious Freedom Restoration Act, or RFRA.

Under that provision, signed into law by President Bill Clinton in 1993, religious institutions can challenge federal laws that put a “substantial burden” on their ability to exercise a sincere religious belief. And if they can prove a substantial burden, then it’s up to the government to show two things: that the law furthers a compelling government interest and that that interest cannot be furthered in any other way that would be less restrictive to religion.

The Obama administration, for its part, has asked courts to dismiss these suits for lack of standing, since the requirement to cover birth control hasn’t started yet. But after it does start, in August 2013 for many of the religious objectors, courts will have to get into the more substantive issues at hand. They would have to answer questions such as: Does requiring insurers to cover contraceptives at religiously affiliated institutions constitute a “significant burden”? Is providing birth control a compelling government interest, and if it is, can it be accomplished in a way that is less restrictive to religion?

Courts haven’t taken up these issues in previous case law, as they relate to the particular issue of providing contraceptives. That makes it difficult for experts to predict how they might rule — and whether these lawsuits could ultimately take down this part of the health reform law.