Mental Illness - As introduced, establishes a rebuttable presumption that a person poses an imminent substantial likelihood of serious harm and needs emergency detention and examination if the person was charged with one of certain criminal offenses and ordered by the criminal, circuit, or general sessions court to undergo an evaluation to determine whether the person is incompetent to stand trial or the person's mental capacity at the time of the commission of the crime; requires clear and convincing evidence to rebut the presumption. - Amends TCA Title 33; Title 40 and Title 52.

HB 625 creates an automatic presumption requiring emergency detention and mental evaluation for defendants charged with specific serious crimes (those carrying 85% mandatory sentence time before parole eligibility) who are ordered by a court to undergo a mental evaluation for competency or mental state at the time of the crime. This presumption can only be overturned by "clear and convincing evidence" showing the person poses no immediate risk of serious harm. The bill directly affects criminal defendants in Tennessee facing certain violent or severe offenses who are undergoing court-ordered mental health assessments. It amends Tennessee law in Titles 33, 40, and 52 to establish this new standard for emergency detention.