The ISLT is also wildly inconsistent with federalism. In our federal system, state courts have the final say over the meaning of state law; states also have considerable latitude in structuring their governments. The ISLT could transform cases about interpreting or applying state election laws into federal constitutional cases to be decided by the federal courts.
The theory would lead to a chaotic system in which states could not reliably hold unified elections for state and federal offices. Common state constitutional provisions guaranteeing that elections be “free,” “free and equal,” or “free and open” would not apply to laws governing federal elections, but would still apply to laws governing state elections.
So, for example, if a state court relied on a state constitutional provision to strike down burdensome registration or voter ID requirements, those requirements would nonetheless remain in place for federal elections. The state would end up with two systems — one for federal elections and one for state elections.