DeBoer v Snyder case is one of only a small number of trials that have ever been held to adjudicate the social science regarding same-sex couples and their children. The DeBoer v Snyder trial decision discredited some arguments against same-sex marriage. The case materials, therefore, may be of historical interest. The transcripts and exhibits below are publicly available on the federal government's court document website, PACER, for a fee. The expert witness reports do not appear to be available on PACER, but they are supposed to be part of the public record, so I have reproduced them here. The PACER record includes many motions that are not reproduced here.
https://web.stanford.edu/~mrosenfe/DeBoer_docs.htm