DES MOINES -- Sen. Rand Paul (R-Ky.) drew immediate criticism from gay rights groups Wednesday after telling an audience at Drake University that there was no need to add protections for gender identity to anti-discrimination statutes.

"I think, really, the things you do in your house, we can just leave those in the house, and they wouldn't have to be part of the workplace, to tell you the truth," Paul said. "These are very difficult decisions, on what you decide will be employers' decisions and not. And it really isn't so much about that question as it is about that it sets a classification, or a class of people, who can now sue."

It's hardly the first time that Paul dismissed gender identity or sexual preference issues as something personal, unwisely thrust into the public square. In an interview with Bloomberg News earlier this year, Paul suggested that rules against transgender people serving in the military could be loosened, but added that the question itself said something disturbing about society.

"I don’t know why we all have to talk about our sex life," he said. "I’m just not interested in other peoples’ — I never go to anybody’s house and everybody wants to talk about it. Why do we have to talk about it?"

At Drake, Paul suggested that more non-discrimination laws could "set up a whole industry for people who want to sue," and it would be better if market forces encouraged people to make unbiased hires.

"People don't put up a sign that says, I'm firing you because you're gay," Paul said. "It's something that's very much disputed. So, I don't know that we need to keep adding to different classifications and say, the government needs to be involved in hiring and firing. I think society is rapidly changing, and if you are gay, there are plenty of places that will probably hire you."

A video of Paul's remarks released by the trackers at American Bridge Wednesday afternoon spurred the Human Rights Campaign to condemn the Kentucky senator, and recall his vote against the Employee Non-Discrimination Act.

"People should not be required to live in the closet or hide who they are in order to be treated equally and fairly under the law,” said JoDee Winterhof, HRC Senior Vice President for Policy and Political Affairs, in a statement. "Rand Paul’s comments do beg the question of whether his fellow candidates will call him out for embracing a platform of discrimination.”