Final answer:
The last state to legalize chiropractic in the U.S was Louisiana in 1974. Regarding the Defense of Marriage Act, the U.S. Supreme Court ruled it unconstitutional in 2013.
Step-by-step explanation:
The last state in the U.S to legalize chiropractic care was Louisiana, which occurred in the year 1974. This question pertains to the history of health regulations and professional licensure in the United States. Chiropractic care, now widely accepted and utilized, was once a controversial and legally disputed practice, with its legal recognition across states being a significant milestone for practitioners and patients who support alternative medicine.
Switching topics, the U.S. Supreme Court ruled the Defense of Marriage Act unconstitutional in the year 2013. This decision was a landmark civil rights ruling that extended federal recognition to same-sex marriages, ensuring equal treatment under federal law for all married couples.