MO SB918

Amends Section 490.065, RSMo to modify standards for expert witness testimony admissibility in Missouri courts

Requires the proponent of expert testimony to demonstrate to the court that "it is more likely than not" that the expert's opinion meets reliability standards, applying to all civil jury trial cases

Changes language from requiring that the "expert has reliably applied" principles and methods to requiring that the "expert's opinion reflects a reliable application of" those principles and methods to case facts

Maintains separate, less stringent standards for expert testimony in family law cases (chapters 451-455), juvenile court proceedings (chapter 211), family court cases (chapter 487), probate proceedings, and non-jury trial actions

Prohibits expert witnesses in criminal cases from opining on whether a defendant had the mental state constituting an element of the crime or defense