Attorney Paul Smith, who successfully argued Lawrence v. Texas before the Supreme Court, summed up several studies in a recent Huffington Post blog post:

Studies that have directly compared gay and lesbian parents with heterosexual parents have consistently shown that the former are as fit and capable as the latter, and that their children are as psychologically healthy and well-adjusted. A 2001 comprehensive survey of peer-reviewed scientific studies concluded that the evidence from empirical research “shows that parental sexual orientation per se has no measurable effect on the quality of parent-child relationships or on children’s mental health or social adjustment.” A more recent review by the same authors noted “the ubiquitous findings of no differences” in comparisons of the families of heterosexual couples with those of lesbian or gay couples. These conclusions are bolstered by three recent studies using national representative samples: one using data from the National Longitudinal Study of Adolescent Health, another using data from the from the Early Childhood Longitudinal Study (Kindergarten Cohort), or the ECLS-K, and the third using U.S. Census data.

These studies are not alone. Major medical organizations have adopted policies supporting gay and lesbian child-rearing. These organizations include: American Psychological Association, American Academy of Pediatrics, The National Association of Social Workers, the American Psychoanalytic Association, the American Psychiatric Association and the American Medical Association. The list goes on.

And there are some incredible numbers that illustrate who gay parents are:

• A typical LGBT parent is more likely to be an African-American woman in Mississippi than a white lawyer in California. U.S. Census Bureau data suggest that Americans raising kids as part of a same-sex couple are almost twice as likely to be African-American as are their counterparts raising children in heterosexual couples, and Mississippi is the state where same-sex couples are most likely to have a child.
• About 3 million LGBT Americans are parents.
• Surveys suggest that 37% of the more than 8 million LGBT adults in the United States report having had a child.
• On average, they’ve had two kids, so it’s likely that at least 6 million Americans have an LGBT parent.

Then there is also the strong testimony revealed during the 2010 Prop. 8 trial, a truth commission on marriage equality, which supports the fact that gay and lesbian couples make great parents. On cross examination by David Boies, the Prop. 8 Proponent’s key witness, David Blankenhorn, testified that some studies suggest that children raised by gay and lesbian parents often fair better than those raised by a straight couple. Check out this video  of John C. Reilly (playing Blankenhorn) and George Clooney (playing David Boies) recreating the testimony. It comes from the play “8,” which is based on the actual trial transcripts:

So what evidence do opponents of marriage equality use to back up their claim? According to Paul Smith, it’s an internet-based study that has been discredited as “non-scientific” by independent audit started by the very journal that published it and denounced by over 200 scientists, clinicians and academics.

Since he took the stand in 2010 David Blankenhorn has changed his view about marriage for gay and lesbian couples. In a June 2012 New York Times op-ed, Blankenhorn concluded that “the time has come for me to accept gay marriage and emphasize the good that it can do.”  “[T]o my deep regret, much of the opposition to gay marriage seems to stem, at least in part, from an underlying anti-gay animus,” Blankenhorn wrote.

• See more highlights >
• Day 12 transcript >

Watch all of the play “8,” based on the actual trial testimony.

AFER’s attorneys objected to Blankenhorn’s qualification as an expert.  The district court agreed, finding Blankenhorn’s opinion testimony to be “unreliable and entitled to essentially no weight.”

Yet, under cross-examination from AFER lead co-counsel David Boies, the witness revealed telling admissions.

• Check out more highlights >
• Read the day’s transcripts >

John C. Reilly reenacted parts of David Blankenhorn’s testimony at the Los Angeles premiere of the play “8,” which also included Brad Pitt as Chief Judge Vaughn R. Walker and George Clooney as attorney David Boies.

AFER’s attorneys objected to Professor Miller’s qualification as an expert in the areas of discrimination against gays and lesbians and gay and lesbian political power.  After hearing his testimony, the district court concluded that Professor Miller “is not sufficiently familiar with gay and lesbian politics specifically to offer opinions on gay and lesbian political power.”

• See more highlights >
• Read the full transcript from day 10 >

• See more testimony highlights >
• Read  all the testimony from day eight >

George Takei reenacted William Tam’s testimony during the Los Angeles premiere of “8” the play.

Ryan Kendell took the stand to talk about his experiences undergoing so-called “ex-gay” or “reparative” therapy.

Parts of Ryan’s testimony were recreated in a powerful scene of the L.A. premiere of “8″ by Glee actor Chris Colfer.

• See more highlights from Ryan Kendell’s testimony >
• Read all of day 7′s testimony >

Gary Segura

Then, Stanford political science professor Gary Segura testified about the political powerlessness of gay and lesbian people in the United States.  Professor Segura explained that gay and lesbian Americans lack a meaningful degree of political power, and possess less political power than other minority groups that have been granted judicial protection.

• More highlights from Dr. Segura’s testimony >

And watch James Pickens, Jr. reenact Professor Segura’s testimony during the Los Angeles premiere of “8” the play.

On the final two days of trial, the anti-marriage proponents of Proposition 8 called David Blankenhorn to testify about marriage and the family.

Blankenhorn is the founder and president of the Institute for American Values, a think tank that studies marriage in America.  AFER’s attorneys objected to Blankenhorn’s qualification as an expert.  The district court agreed, finding Blankenhorn’s opinion testimony to be “unreliable and entitled to essentially no weight.”

Under cross-examination by AFER attorney David Boies, Blankenhorn admitted under oath that “I believe that today the principle of equal human dignity must apply to gay and lesbian persons.  In that sense insofar as we are a nation founded on this principle, we would be more American on the day we permitted same-sex marriage than we were on the day before.”

In a June 2012 New York Times op-ed, Blankenhorn concluded that “the time has come for me to accept gay marriage and emphasize the good that it can do.”  “[T]o my deep regret, much of the opposition to gay marriage seems to stem, at least in part, from an underlying anti-gay animus,” Blankenhorn wrote.

John C. Reilly reenacted David Blankenhorn’s testimony at the Los Angeles premiere of the play “8,” which also included Brad Pitt as Chief Judge Vaughn R. Walker and George Clooney as attorney David Boies.

Testimony Highlights

“The studies show that adoptive parents, because of the rigorous screening process that they undertake before becoming adoptive parents, actually on some outcomes outstrip the biological parents in terms of providing protective care for their children.”

“Gay marriage would be a victory for the worthy ideas of tolerance and inclusion.”

“I believe that adopting same-sex marriage would be likely to improve the well-being of gay and lesbian households and their children.”

“By increasing the number of married couples who might be interested in adoption and foster care, same-sex marriage might well lead to fewer children growing up in state institutions and more growing up in loving adoptive and foster families.”

“Because marriage is a wealth-creating institution, extending marriage rights to same-sex couples would probably increase wealth accumulation and lead to higher living standards for these couples as well as help reduce welfare costs (by promoting family economic self-sufficiency) and decrease economic inequality.”

“Gay marriage might contribute over time to a decline in anti-gay prejudice as well as, more specifically, a reduction in anti-gay hate crimes.”

“Same-sex marriage would likely contribute to more stability and to longer-lasting relationships for committed same-sex couples.”

“Gay marriage would extend a wide range of the natural and practical benefits of marriage to many lesbian and gay couples and their children.”

“Extending the right to marry to same-sex couples would probably mean that a higher proportion of gays and lesbians would choose to enter into committed relationships.”

On the tenth and eleventh days of trial, the proponents of Proposition 8 called Kenneth Miller, a professor of political science at Claremont McKenna College, as an expert in American and California politics.  Plaintiffs objected to Professor Miller’s qualification as an expert in the areas of discrimination against gays and lesbians and gay and lesbian political power.  After hearing his testimony, the district court concluded that Professor Miller “is not sufficiently familiar with gay and lesbian politics specifically to offer opinions on gay and lesbian political power.”

Testimony Highlights

“In my view, gays and lesbians have the ability to attract the attention of lawmakers in California.”

“[DAVID BOIES]: I want to be sure I understand what you are saying. You are saying that there is official discrimination, like the ‘Don’t ask, Don’t tell’ policy, correct?

“[KENNETH MILLER]: Umm —

“[BOIES]: That’s what you refer to as official discrimination?

“[MILLER]: It’s legally enforced rules that have an effect on gays and lesbians, which is different than heterosexual people, yes.

“[BOIES]: And that’s what you refer to as official discrimination, is that true? I’m just trying to get your word –

“[MILLER]: Maybe ‘legal’ is a better word. It’s — or de jure. I don’t know how you want to describe it. Various different ways to describe the same thing.

“[BOIES]: What word is the word you use? Because I just want to use your language.

“[MILLER]: Okay. ‘Official’ would be fine.

“[BOIES]: ‘Official,’ okay. And by official discrimination, you mean discrimination that is legally enforced, discrimination by the state, correct?

“[MILLER]: I think that’s fair to say, yeah.

“[BOIES]: Now, are you aware of any of what you call official discrimination against gays and lesbians in this country today other than the ‘Don’t ask, Don’t tell’ policy?

“[MILLER]: I’m just trying to think of other laws or official policies that discriminate on that basis.”

“I haven’t looked closely to see if there are any examples where sexual orientation would be a factor in terms of the workplace. I can’t think of any.”

“[BOIES]: Do you believe that gays and lesbians are still the object of prejudice and stereotype, today?

“[MILLER]: I think like a lot of groups they are, yes.

“[BOIES]: I’m sorry. Say that again?

“[MILLER]: I think like a lot of groups, they face some stereotyping and some prejudice.”

“[BOIES]: And have you investigated how many gays and lesbians are fired from their jobs, refused work, paid less, and otherwise discriminated against in the workplace simply because they are gay or lesbian? Have you investigated that?

“[MILLER]: The total number, no, I have not.

“[BOIES]: The approximate number, have you looked at that?

“[MILLER]: No, I have not.

“[BOIES]: Have you tried to find out whether that number is large or small?

“[BOIES]: I assume it’s a substantial number. I haven’t looked at the specific numbers.”

“My view is that at least some people voted for Proposition 8 on the basis of anti-gay stereotypes and prejudice.”

“I think there might be circumstances where political science generally would be quite disposed to agree with a religiously-based argument that might be held by a majority, but, again, I think the principle you are driving at is that would political science in general believe it is inappropriate or undesirable for a religious majority to impose on a religious minority its views. And I think probably a majority of political scientists would agree with that.”

On the ninth day of trial, Gregory Herek, a professor of psychology at the University of California, Davis, testified about sexual orientation and social stigma.  His testimony addressed the psychological and psychiatric understanding of sexual orientation, whether an individual’s sexual orientation can be changed, and Proposition 8’s relation to stigma and prejudice.

Professor Herek is the author, editor, or co-editors of several books and articles, including Stigma and Sexual Orientation: Understanding Prejudice against Lesbians, Gay Men and Bisexuals and Out in Force: Sexual Orientation and the Military.

Watch Rory O’Malley’s reenactment of Professor Herek’s testimony from the Los Angeles premiere of “8” the play.

Testimony Highlights

“[S]exual orientation is at its heart a relational construct, because it is all about a relationship of some sort between one individual and another, and a relationship that is defined by the sex of the two persons involved.”

“[These] sorts of relationships, that need for intimacy, that need for attachment, is a very core part of the human experience, and a very fundamental need that people have.”

“[H]eterosexual and homosexual behaviors alike have been common throughout human history.”

“I’ve conducted research that—in which I found that the vast majority of lesbians and gay men, and most bisexuals as well, when asked if they feel that they—show much choice they’ve had been their sexual orientation, about being gay or lesbian or bisexual, say that they have experienced no choice or very little choice about that.”

“It’s my opinion that the current research does not indicate that interventions that are designed for that purpose have been shown to be effective using the criteria that I described this morning.

“It certainly is the case that there have been many people who, most likely because of societal stigma, wanted very much to change their sexual orientation and were not able to do so.”

“Well, the American Psychiatric Association, the American Psychological Association, and other of the—of the major professional mental health associations, have all gone on record affirming that homosexuality is a normal expression of sexuality, that it is not in any way a form of pathology.”

“[S]exual orientation is really about the relationships that an individual forms. It really defines the universe of people with whom one is going to be able to form the sort of intimate, committed relationship that would be the basis for marriage.”

“[J]ust the fact that we’re here today suggests that this is more than just a word … clearly, [there is] a great deal of strong feeling and emotion about the difference between marriage and domestic partnerships.”

“Well, I think that if we—if we look at, for example, public opinion data, what we see is that there’s a sizable proportion of the public, both in California and in the United States, who say that they are willing to let same-sex couples have domestic partnerships or civil unions or some—something that gives them the benefits of marriage without calling it marriage.

“And, yet, they are not—they are willing to extend those benefits, but they are not willing to extend marriage to same-sex couples, which suggests that in the minds of a large number of—of Americans, there is some distinction between domestic partnerships and marriage; that it’s not simply a word, that there’s more to it than that.

“I think, also, if we look at the recent history of California, when it became possible for same-sex couples to marry, thousands of them did. And many of those who did were domestic partners. So, clearly, they thought there was something different about getting married.

“And I would say that just the fact that we’re here today suggests that this is more than just a word; that there’s, clearly, a great deal of strong feeling and emotion about the difference between marriage and domestic partnerships.”

On the eighth day of trial, Hak-Shing William Tam, an official proponent of Proposition 8, was called as an adverse witness by plaintiffs.  He testified about the messages he disseminated during the Proposition 8 campaign.

Watch George Takei reenact William Tam’s testimony during the Los Angeles premiere of “8” the play.

Testimony Highlights

“I think it’s very important for the next generation to understand the historical meaning of marriage. It is very important that our children won’t grow up to fantasize or think about, Should I marry Jane or John when I grow up?”

“[I]f ‘domestic partner’ is defined as it is now, then we can explain to our children that, yeah, there are some same-sex person wants to have a lifetime together as committed partners, and that is called ‘domestic partner,’ but it is not ‘marriage.’ Then we have something that is very easy for our children to understand.”

“[DAVID BOIES]: What I’m trying to get at, and I will be really clear, is that children of gays and lesbians want their parents to be married, just like children of heterosexual couples want their parents to be married, because the word “marriage” means something, correct? You may think they shouldn’t have it –

“[WILLIAM TAM]: Yes.

“[BOIES]: (Continuing) — okay? You may think they shouldn’t have it for all sorts of reasons, but you recognize that that’s important to those children, correct?

“[TAM]:  Yes.”

“[BOIES]: Now, do you believe that homosexuals are 12 times more likely to molest children? Do you believe that?

“[TAM]: Yeah, based on the different literature that I’ve read.”

“[BOIES]: Okay. Now, [on your website] you go on to say that: ‘If Proposition 8 loses, one by one other states would fall into Satan’s hand.’  Do you see that?“[TAM]: Yes.

“[BOIES]: And by falling into Satan’s hand, you meant permitting gays and lesbians to marry, correct?

“[TAM]: Yes.”