An elite French institution was expected to rule Friday on whether President Emmanuel Macron’s contested plan to raise the retirement age is constitutional, a decision that could calm or further enrage opponents of the change.

All eyes were on the heavily guarded Constitutional Council, which can nix all or parts of a complex pension reform plan that Macron pushed through without a vote by the lower house of parliament. Spontaneous demonstrations were likely around France ahead of the nine-member court’s ruling.