Based on the totality of the circumstances, appellant’s statements to police officers were voluntary and therefore admissible at his trial for attempted murder. The fact that the officer made an improper promise of leniency by advising appellant that his cooperation would benefit him was not sufficient to render the otherwise voluntary statements involuntary. Further, the exclusion of expert testimony on police interrogation tactics did not require reversal. The trial court properly concluded that the defense failed to demonstrate the need for the expert testimony, and also expressly indicated that it would reconsider during trial if the evidence adduced at trial suggested that the expert testimony was relevant. However, the matter had to be remanded for resentencing because the 186.22 enhancement required a 15-year service of a term, not a 15-year enhancement, and a consecutive term could have properly been imposed as to count 2 for a total of two life terms with a minimum term of 30 years before parole eligibility, plus 20 years. The court declined to impose an additional term and increase the sentence substantially without permitting the trial court to exercise its discretion in the first instance. Therefore, remand was required.