Alabama Attorney General Luther Strange today filed a brief with the U.S. Supreme Court in support of laws that ban same-sex marriages in Kentucky, Michigan, Ohio and Tennessee.

Strange urges the court to uphold an appeals court decision that found those state's marriage laws to be constitutional.

The justices are expected to hear the case beginning April 28 and are expected to rule later this year.

The case involves whether the 14th Amendment requires states to license same-sex marriages and recognize those marriages done in other states.

In a news release, the attorney general's office said the brief was written in partnership with the Alliance Defending Freedom, a conservative, nonprofit legal group, at no cost to the taxpayers.

In the brief, they argue that the Supreme Court has to uphold states' same-sex marriage bans if they are based on a legitimate state interest.

They say it's in the state's interest to promote ties between children and both of their biological parents and that traditional marriage laws support that.

Strange said the case has implications beyond marriage because it could affect whether federal courts can overturn other decisions by states.

"The presumption is state laws are constitutional," Strange said. "If the traditional definition of marriage is not a rational basis for legislative action, it is hard to imagine what is."