Not a complete wall between branches of government, and not a rule that keeps them from interacting at all. The idea is that government power is divided among separate branches so no single branch controls everything. In the United States and in the states, that usually means the legislative branch makes laws, the executive branch carries them out, and the judicial branch interprets and applies them in actual disputes. Each branch has its own role, even though they still check and limit one another.

That division matters in everyday legal problems because different parts of government handle different parts of the same issue. A legislature may set the rules for damages, filing deadlines, or claims against the government. An agency in the executive branch may investigate safety failures or enforce regulations. A court decides whether those rules apply in a particular personal injury case and whether a party's rights were violated.

In North Carolina, this principle is written into the North Carolina Constitution, Article I, Section 6, which states that the legislative, executive, and supreme judicial powers shall remain separate and distinct. In an injury claim, that can affect who has authority to act: lawmakers can change the law, but judges cannot rewrite it, and agencies cannot decide cases beyond the power the law gives them. That matters when a crash, including a fog-related pileup on I-40 near Asheville, leads to disputes over responsibility, immunity, or the reach of a safety rule.