Tidbit from TPM:

Rev. Johnson is insinuating that if the Stricklands really weren't gay, why, they'd file a lawsuit and go to court so they could prove it and clear their good name. Until that happens, Johnson says, he's "withholding judgment" on the Stricklands' sexuality.

The Columbus Dispatch has more:

In an interview Thursday, Johnson perpetuated the rumor by suggesting that the Stricklands file a lawsuit and go to court to prove they are heterosexuals. If Lankford's claim is untrue, Johnson said, "It's slanderous and they've got a case. I'm withholding judgment until the facts are in."

When it comes to the Stricklands' sexual orientation, it appears that for some Ohio Republicans, the burden of proof lies with the Stricklands.