He, Ken Paxton, said so in an interview with NewsNation. His announcement comes shortly after the Supreme Court's abolition of the nationwide abortion law in the US. That right was obtained by a ruling of that Court on the basis of privacy rights. The legalization of homosexuality and same-sex marriage rests on a similar principle.
Should Texas pass a "sodomy law," a law banning homosexuality, it would have to be defended in court. The final station in such a trajectory is the Supreme Court. The support of the Texas Attorney General, who has to defend the law, is therefore important.
Now that the Court has a "super-majority" of six conservative judges, there is a chance that gay rights, like the right to abortion, will be on the chopping block. Conservative Chief Justice Clarence Thomas has already expressed his support for the abolition of gay rights. Paxton shares that view. In his view, the constitution says nothing about gay rights, so according to him it is up to the legislator to protect rights and not the court.
Whether Texas will actually introduce a sodomy law remains to be seen. Currently, the topic is not a priority for Republicans there, but the support of the Attorney General could be a step in that direction.