A highway is any public street, road, turnpike or canal which any member of the public has the right to use. Highways are distinguished from private roads in that highways are intended for public use, and are maintained at the public's expense. Both state and federal laws regulate highways. Laws cover such issues as safe driving, public transportation, liability of highway officials for damage caused by construction and repair, transportation of hazardous materials, and more. The privilege of using a public highway carries certain legal obligations, such as having a driver's license if operating a vehicle and obeying speed limits. Special regulations apply to commercial users of highways.
State and federal Departments of Transportation jointly regulate and fund highways. Often the mandates legislated on the federal level are enforced at the state level, and such state compliance ensures availability of federal transportation funding. For example, states that enforce the federal blood alcohol concentration limit of .08 percent, are eligible for federal funding that states with higher limits are not.
