February 2016 | The South Dakota Legislature approved a bill that would require public school students to use bathrooms and other facilities that correspond to their biological sex, defined in the bill as “a person’s chromosomes and anatomy as identified at birth.” Gov. Dennis Daugaard, a Republican, vetoed it. The Legislature announced in January that it would consider a similar bill.

North Carolina bans local anti-discrimination policies

March 23, 2016 | Meeting in special session, North Carolina legislators passed a wide-ranging bill known as House Bill 2 barring transgender people from bathrooms and locker rooms that did not match their biological sex. Republicans unanimously supported the bill, while in the Senate, Democrats walked out in protest. “This is a direct affront to equality, civil rights and local autonomy,” the Senate Democratic leader, Dan Blue, said in a statement.

The bill’s passage prompted the N.B.A. to withdraw this season’s All-Star Game from Charlotte and led the N.C.A.A. to move playoff games in several sports — including first- and second-round games in its most prominent event, the Division I men’s basketball tournament — out of the state.

The federal government issues guidelines

May 12, 2016 | The Obama administration took up a legal fight with North Carolina over the issue, quickly issuing guidance — signed by Justice and Education Department officials — that was sent to all school districts, outlining what schools should do to ensure that no student was discriminated against. The letter did not have the force of law, but it contained an implicit threat: Schools that did not abide by the Obama administration’s interpretation of the law could face lawsuits or a loss of federal dollars. The measure attracted criticism and support from across the country.

A split emerges between Southern cities and states