Danaher v. Smith, 666 S.W.2d 452, 456 [3, 4] (Mo.App. 1984). Though State v. Hodges, 586 S.W.2d 420, 425[6] (Mo.App. 1979), refers to the question as one of privilege, in this case there was no privileged husband-to-wife communication in issue. Rather, the question is one of what class of person is competent to testify, and therefore the statute deciding that question vested no substantive rights.
However, if the Court fails to indicate in the decision creating the new rule whether that rule is to be applied retrospectively or prospectively, then this determination hinges on whether the new rule of law is procedural or substantive. Shepherd v. Consumers Cooperative Association, 384 S.W.2d 635, 640 (Mo. banc 1964); Barker v. St. Louis County, 340 Mo. 986, 1001, 104 S.W.2d 371, 377-78 (Mo. 1937); Koebel v. Tieman Coal Material Co., 337 Mo. 561, 570-71, 85 S.W.2d 519, 524 (Mo. 1935); State v. Hodges, 586 S.W.2d 420, 425 (Mo.App. 1979); Durham v. State, 571 S.W.2d 673, 676-77 (Mo.App. 1978). If the new rule is procedural, it is given prospective application only. Moore v. Ready Mixed Concrete Company, 329 S.W.2d 14, 24 (Mo. banc 1959). If the new rule is substantive, it is given both retrospective and prospective application. Dietz v. Humphreys, 507 S.W.2d 389, 392 (Mo. 1974); Roth v. Roth, 571 S.W.2d 659, 671-72 (Mo.App. 1978).
It is not error for a prosecutor to refer to evidence in an opening statement, even if that evidence is later excluded, if the evidence mentioned is arguably admissible and the prosecutor acts in good faith—with reasonable grounds for believing he will be able to introduce such evidence. McFadden , 391 S.W.3d at 430 ; State v. Debler , 856 S.W.2d 641, 656 (Mo. banc 1993) ; State v. Hodges , 586 S.W.2d 420, 426 (Mo. App. E.D. 1979). In contrast, a prosecutor commits error if he acts in bad faith by deliberately promising proof of evidence which is altogether inadmissible.
The trial court sustained appellant's objection to this line of argument and instructed the jury to disregard the comment. What this court stated in State v. Hodges, 586 S.W.2d 420 (Mo.App. 1979) regarding a claim that only a mistrial would cure an improper argument applies with equal force here: The trial court, however, has broad discretion in deciding whether improper argument necessitates a mistrial.
The state should not apply personal epithets to a defendant or otherwise abuse him in such a manner to inflame the jury or appeal to prejudice. State v. Hodges, 586 S.W.2d 420 (Mo.App. 1979). However, what may appear to be an epithet, may constitute the expression of a conclusion urged upon the basis of the evidence.
Motive can be important in a murder case based on circumstantial evidence, but it is not an element of the crime. State v. Hodges, 586 S.W.2d 420, 429 (Mo. Ct. App. 1979). Further, there was evidence from which the jury could have inferred motive.
When the issue concerns the trial court's exercise of discretion relative to opening statements, no error requiring reversal will be found if a challenged statement refers to arguably admissible evidence and the reference was made in good faith with a reasonable expectation the evidence will be produced. State v. Browner, 587 S.W.2d 948, 952-53 (Mo. App. 1979); State v. Hodges, 586 S.W.2d 420, 426 (Mo.App. 1979); State v. Thomas, 526 S.W.2d 893, 896 (Mo.App. 1975). Here evidence as to the informant's observations was "arguably admissible", as the officer's testimony was offered not to prove that the information received was true but rather to explain his surveillance of the house.
Rules proscribing testimony because of privilege are not considered substantive but rather procedural rules of evidence pertaining to exclusion of particular testimony. State v. Hodges, 586 S.W.2d 420, 425 (Mo.App. 1979). Such procedural changes are given prospective effect only, Barker v. St. Louis County, 340 Mo. 986, 104 S.W.2d 371, 377-78 (1937); Dietz v. Humphreys, 507 S.W.2d 389, 392 (Mo. 1974), and in appropriate cases substantive changes too may be made prospective.
Motive can be important in a murder case based on circumstantial evidence, but it is not an element of the crime. State v. Hodges, 586 S.W.2d 420, 429 (Mo.App. 1979). Further, there was evidence from which the jury could have inferred motive.
However, a prosecutor can refer to a defendant as a bum if the facts of the case show that he was in fact, an indigent transient, State v. Gartrell, 171 Mo. 489, 71 S.W. 1045 (1903), brandish a butcher knife alleged to be defendant's, State v. Luallen, 654 S.W.2d 226, 228 (Mo.App. 1983), employ a degree of dramatics, State v. Edmonds, 347 S.W.2d 158 (Mo. 1961). Although generally speaking the use of the word "monster" in the context of an opening statement is erroneous, State v. Hodges, 586 S.W.2d 420, 427 (Mo.App. 1979), it was not so prejudicial as to require reversal under plain error review. See Rule 30.20.