Christopher Carpenter, an associate professor of economics and public policy at UC Irvine, discussed Tuesday his latest research, which finds — among other things — that legal recognition of same-sex marriage affects homosexuals’ choices to marry but does not lead to a decline in heterosexual marriage.

Just married · Christopher Carpenter, an associate professor of economics and public policy at UC Irvine, discussed the effects of gay marriage in Massachusetts on nationwide equality trends during an event Tuesday. – Chris Roman | Daily Trojan

Carpenter spoke at an event hosted by USC’s Center for Health Policy and Economics as part of its Quintiles Health Policy Seminar Series. His research, which examines the effects of legalizing same-sex marriage, focused on the states of California and Massachusetts.

In Massachusetts, Carpenter said gay marriage has had no effects on the marital rates of straight women.

“There are no negative deleterious effects on heterosexual marriages, at least as measured by the proportion of women that get married,” Carpenter said.

He said his research found an increase in the rate of lesbians who identify themselves as married after Massachusetts legalized gay marriage.

“Legalized same-sex marriage induced both bisexual women and lesbian women, particularly bisexual women, to tie the knot,” Carpenter said. “There is some proportion of lesbian women who say that they are married even in the period when [same-sex marriage] was not legal, and those are probably people in long-term relationships, who consider [themselves] married.”

His findings showed a similar trend in marriage rates for men, Carpenter said.

Carpenter’s presentation covered a wide range of issues concerning same-sex marriage, including data showing differences between male and female LGBT populations.

One such difference was the differences in marriage rates of gay men and lesbians. Carpenter referred to a graph that showed a greater increase in lesbian marriages than in marriages of gay men.

“This basically says that gay guys don’t formalize,” Carpenter said. “So lesbians formalize and gay guys don’t.”

One reason for this trend, Carpenter suggested, is that lesbian women are more likely to have children in their household compared to gay men.

“Legal benefits to marriage if you have kids are enormous, whereas the legal benefits if you don’t have kids … are not as large,” Carpenter said. “So that’s what we think is going on as to why the lesbian increase is way bigger than the gay increase.”

He also pointed out bisexuals were a minority among the male LGBT population, but not the female population.

The presentation followed a free-flowing format where those in attendance were allowed to ask about research and make suggestions for improvements that could be made to his research. Carpenter’s research is not yet complete but will be published shortly after its finalization.