Iowa Representative Steve King, a Republican, on Thursday suggested that a Supreme Court ruling striking down state bans on gay marriage could lead to civil war.

The nation's highest court heard arguments in a case challenging bans in Ohio, Tennessee, Michigan and Kentucky on April 28. A ruling, which could lead to nationwide marriage equality, is expected in the next week.

Speaking to social conservatives gathered this week at the Faith and Freedom Coalition's Road to Majority conference, King warned that a ruling that doesn't uphold the bans could lead to civil unrest, much like the high court's 1857 Dred Scott decision that upheld slavery.

“Well, that turned into a civil war – 600,000 people killed to put an end to slavery – to sort that mess out,” King said.

He went on to compare the pending decision to Roe v. Wade, the 1973 case that found women have a right to abortion.

“Fast forward to Roe v. Wade, 1973, and what happens with that? The Supreme Court decides they are going to decide for us a huge social question, not rooted in law or the constitution,” King said. “They made it up as they went along, and what happens? We march every year until we come back to celebrate the end of Roe v. Wade.”