States that license polygraph examiners:
Alabama
Arkansas
Illinois
Indiana
Iowa
Kentucky
Louisiana
Maine
Massachusetts
Michigan
Mississippi
Missouri (only needed in St. Louis County)
Nebraska
Nevada
New Mexico
New York (only needed in Erie & Suffolk Counties)
North Carolina
North Dakota
Oklahoma
Oregon
South Carolina
South Dakota
Tennessee
Texas
Utah
Vermont
Virginia
West Virginia
(from the www.AmericanPolygraphAcademy.com Licensing page)