The bill makes it illegal for trans people to use a gender appropriate bathroom in many public places.
It also rolled back local ordinances protecting LGBT people against discrimination and banned local authorities from re-introducing them.
“H.B. 2 denies transgender people access to sex-segregated bathrooms and changing rooms consistent with their gender identity unless they can produce an amended birth certificate,” said the Department.
“Excluding transgender men and women from bathroom and changing facilities consistent with their gender identity causes significant and irreparable physical, psychological, economic, social and stigmatic harm to transgender people,” the Justice Department adds.
The so-called “safety concerns” on which the criticism of HB2 are based are “factually baseless and legally insufficient to justify this discrimination,” the memo continues.