Lamb's expertise has influenced legal decisions addressing same-sex parenting, advocating for fostering and adoption by adults regardless of their marital status or sexual orientations.
Lamb conducted a comprehensive longitudinal study on early family relationships, laying the groundwork for his influential work on children's development.
Ed Zigler also played an important role in supporting Lamb’s work at this time, reinforcing the significance of bridging theory and practice and conducting rigorous research.
[8] Lamb's research on children's adjustment after divorce shed light on the psychological and emotional effects of parental separation.
[9] Lamb has served as an expert witness in court cases challenging prohibitions against fostering or adoption of children by individuals with same-sex sexual orientations.
Lamb's testimony about the importance of parent-child relationships, regardless of family structure, played a crucial role in U.S. litigation on same-sex marriage, including cases considered by the U.S. Supreme Court in 2014.
[4] In 2010 Michael Lamb was to testify in the Perry v. Schwarzenegger trial which challenged the constitutionality of California Proposition 8 against same-sex marriage.
[3] In collaboration with Philip Hwang, Lamb conducted a pioneering longitudinal study examining the effects of different childcare patterns on Swedish children's development.
[4][18] Lamb’s research involved close collaboration with professionals responsible for conducting investigative interviews of alleged abused children in Israel.
[19] This stimulated the development of a protocol which would aim to improve the reliability of child witness capabilities, especially in cases of sexual and physical abuse.