Kentucky Governor Steve Beshear, a Democrat, has defended arguments used in defending the state's ban on gay marriage.

The state's arguments have been criticized as “absurd” and “irrational.”

On Tuesday, U.S. District Court Judge John G. Heyburn II dismissed the arguments as “not those of serious people.”

(Related: Federal judge strikes down Kentucky's gay marriage ban.)

In response to plaintiffs' motion for summary judgment, Beshear's hired counsel argued that Kentucky's ban was needed to protect the human race and was “consistent with sound economic policy.”

“It is axiomatic that procreation is vital to continuation of the human race and that only man-woman couples can naturally procreate,” the brief states. “Encouraging, promoting, and supporting the formation of relationships that have the natural ability to procreate furthers the Commonwealth's fundamental interest in ensuring humanity's continued existence.”

“The continued expansion of the population through stable birth rate growth fosters long-term economic stability, unquestionably a valid state interest. One need look no further than economic journals and news sources to see the correlation between a society's birth rates and its long term ability to support a strong economy.”

Beshear was asked to respond to the criticism at an unrelated press conference.

“The job of the lawyers on both sides is to get every argument out in front of the court so they can make a reasonable decision,” he answered.

He also declined to state his personal stance on marriage equality.

“My sole purpose for filing this appeal is that every Kentuckian deserves to get an answer on this very difficult and controversial issue,” Beshear said. “Whatever the law of the land is, Kentucky is going to abide by it.”