The 1963 Supreme Court case Gideon v. Wainwright enforced the right for legal counsel during a trial and helped form the basis of our legal system today.

Sources

https://www.landmarkcases.org/cases/gideon-v-wainwright

https://www.floridasupremecourt.org/Law-Library/Historical-Documents-Rare-Books/Gideon-v.-Wainwright

https://www.oyez.org/cases/1962/155

https://www.uscourts.gov/educational-resources/educational-activities/facts-and-case-summary-gideon-v-wainwright

https://www.britannica.com/event/Gideon-v-Wainwright

https://www.youtube.com/watch?v=1U_mpTQnKVI&t=224s