SB 1431 proposes modifications to the eligibility criteria for participation in certain drug court programs established under Chapter 123 of the Government Code. The bill allows juveniles involved in delinquent conduct or conduct needing supervision, where substance use significantly contributed to the offense, to participate in drug court programs unless the offense involved the use of a firearm, caused death, or resulted in serious bodily injury, without the state's attorney's consent. Additionally, the bill requires counties with populations exceeding 200,000 to establish adult drug court programs. It specifies that these changes apply to juveniles entering such programs, regardless of when the conduct occurred, with an effective date of September 1, 2025.