INDIANAPOLIS -- Indianapolis-based drugmaker Eli Lilly and Co. is telling lawmakers that it opposes a proposed constitutional amendment banning same-sex marriage in Indiana, saying it could negatively impact employee recruitment.

In a letter to state House Speaker Pat Bauer, D-South Bend, Lilly said the proposal sends an unwelcoming signal to current and future employees by making Indiana appear intolerant.

Lilly also said employees are concerned that the plan might endanger current domestic partner benefits.

The measure's sponsors responded by saying that Lilly doesn't know what it is talking about, 6News' Norman Cox reported.

State Rep. Eric Turner, R-Gas City, said that when companies testified against the bill during an earlier legislative committee meeting, he asked them whether they could identify any state that had to eliminate domestic partnership benefits after passing a constitutional same-sex marriage ban.

"They could not identify one. In fact, they said there were none," Turner said.

Indiana's proposed amendment has two sections. The first states that marriage in Indiana is the union of one man and one woman. The second provision includes a phrase that says state law "may not be construed to require that marital status or the legal incidents of marriage be conferred upon unmarried couples or groups."

Some opponents say the second provision is vague and could be used to nullify domestic violence laws that apply to married and unmarried couples. They also fear it could eliminate domestic partner benefits offered by some companies, universities and other employers.

Supporters of the amendment say the second provision simply means courts cannot force the government to provide same-sex benefits. They say it does not prohibit the government, public employers or anyone else from voluntarily offering such benefits.

Amending Indiana's constitution requires a resolution to pass consecutive, separately elected General Assemblies and then be approved in a statewide vote. The Legislature passed the proposal in 2005, so if it is approved this year or in 2008, it could appear on the November 2008 ballot.