"So if there is something on there that they know is false, then they would be eligible to be charged with making a false statement or committing perjury, which is a Class D felony," Coffey said.
A Class D felony carries a possible penalty of six months to three years in jail and a possible fine of up to $10,000.
Indiana's current electronic marriage license application specifically designates "male applicant" and "female applicant" sections for gathering required background information. Coffey says that means if two men or two women applied for a marriage license, one of them would commit perjury.
"In Indiana the law clearly states that one man and one woman are the only two who can apply for a marriage license and can have a marriage ceremony performed," Coffey said.
Same-sex marriage advocates said the law isn't fair.
"When our government doesn't support us, the (lesbian-gay-bisexual) community, and we have all of these gay-straight alliances pop up, and you have all of these bullying issues, what type of message does that send to our children?" said Ashley Smith of Pride Lafayette.
The Indiana General Assembly is expected next year to try to write the state's gay marriage ban into the constitution, a move that would need approval from voters in a statewide referendum.