OPINION
BIVINS, Judge.
Defendant, a pathologist, appeals his convictions on five counts of criminal sexual contact of a minor (CSCM), two counts of criminal sexual penetration (CSP), and one count of extortion, all involving one adolescent victim. He makes the following claims on appeal: (1) ineffective assistance of counsel in (a) failing to diligently investigate an alibi, (b) failing to object to evidence of prior bad acts involving other adolescents, and (c) failing to object to allegedly improper closing argument; (2) trial court error in (a) permitting the State to amend the indictment at trial in light of the court’s simultaneous denial of Defendant’s request for a continuance to investigate possible alibi witnesses, (b) denying Defendant’s motion in limine to exclude evidence of uncharged misconduct involving Defendant’s two sons; (3) reversible error resulting from the prosecutor’s closing argument; (4) reversible error resulting from missing exhibits; and (5) cumulative error resulting in denial of a fair trial. We affirm.
BACKGROUND
Defendant was indicted on numerous counts involving a single adolescent victim. The indictment included two counts of extortion, twelve counts of CSCM, one count of kidnapping, and seven counts of CSP. Defendant admitted to having a sexual relationship with the victim. That fact was not at issue. The primary issues centered around when some of these activities occurred and, most importantly, whether they all occurred consensually or as a result of Defendant’s improper use of his position of authority to coerce the victim. It is important to keep in mind that the defense strategy was to openly and forthrightly reveal Defendant’s sexual problems in an attempt to convince the jury that he did not coerce the victim. In short, Defendant presented himself as powerless over his addiction to deviant sexual behavior and felt it important to divulge this sickness. This strategy was not altogether unsuccessful. The jury acquitted Defendant on many of the charges.
1. Ineffective Assistance of Counsel
After trial, Defendant employed new counsel to pursue a motion to reconsider denial of a motion for a new trial, and also to handle this appeal. Although Defendant presents his claims of ineffective assistance of counsel under several different points, we discuss them together. We apply the standards set forth in State v. Crislip, 109 N.M. 351, 353-54, 785 P.2d 262, 264-65 (Ct.App.), cert. denied, 109 N.M. 262, 784 P.2d 1005 (1989).
a. Failing to Investigate Alibi
Under the State’s charges, Defendant’s sexual activities with the victim occurred during four time periods. The second time period was described in the indictment as being “on or about August 22,1987.” During trial, after the victim testified, it became apparent that the date should have been August 25 rather than August 22. The State successfully moved to amend the pertinent counts of the indictment. The trial court denied Defendant’s request for a continuance to investigate possible alibi witnesses for August 25.
Defendant claims his counsel was ineffective for failing to discover, prior to trial, his exact whereabouts on August 25, 1987, the date of the second series of alleged sexual encounters with the victim. After trial, counsel was able to find telephone and hospital records that indicated Defendant did not arrive at the hospital, the location of the alleged encounters, until 6:00 p.m. on that day and was in a staff meeting for part of the evening. Defendant moved for a new trial, alleging newly discovered evidence and adding the ineffective assistance of counsel claim. After an evidentiary hearing on the motion, the trial court denied it, stating that the new evidence would not change the result of the trial because, although it established Defendant’s whereabouts on August 25, the victim’s whereabouts on that date were never clear. In other words, even with the new evidence the jury could have found that the victim and Defendant were at the hospital at the same time.
It is clear that counsel could have discovered, prior to trial, the more detailed information about his client’s activities on August 25. However, counsel’s testimony at the hearing on the motion for new trial established that he had good reasons for failing to do so, so that the failure did not constitute ineffective assistance. First, Defendant himself had told counsel that the hospital did not have staff meetings during the summer, and did not tell counsel of that particular staff meeting. Also, August 25 was after school started for the victim, and the victim’s pretrial statements indicated he did not work at the hospital after school began, and that he was last at the hospital on August 21, for a banquet. Counsel therefore focused on the victim’s whereabouts and not on Defendant’s. Counsel also tried to determine whether there was a record at the hospital that would establish when the pathologists were at the hospital and in the laboratory, and was told there was no such record. At the hearing, counsel testified that “[y]ou could characterize it that the defendant forgot to tell me he was at the meeting,” so that counsel believed there was no meeting. At the same time, counsel also believed that no one remembered where they were on August 25, 1987, and that no records existed with which they could refresh their memories. All of this establishes that the failure to more fully develop Defendant’s whereabouts was caused partly by Defendant’s own misstatements to counsel, and partly by counsel’s strategic decision to focus on the victim’s location rather than Defendant’s.
Under these circumstances, we do not believe that the trial court was compelled to find ineffective assistance of counsel. See State v. Dean, 105 N.M. 5, 8, 727 P.2d 944, 947 (Ct.App.) (this court will not attempt to second-guess tactics and strategy of trial counsel), cert. denied, 104 N.M. 702, 726 P.2d 856 (1986).
b. Failing to Object to Prior Bad Acts Evidence
The trial court conducted a pretrial hearing on Defendant’s motion in limine to exclude evidence of prior bad acts involving a number of adolescent males, including Defendant’s two sons, all of whom had been named by the State as witnesses. At the hearing, the defense put on evidence through Dr. Dougher, a clinical psychologist specializing in treatment of sex offenders. This testimony previewed much of what would be offered by the defense at trial. Dr. Dougher stated that it was his opinion that Defendant is a homosexual hebephile and that, based on a review of extensive records, including records of sexual activities between Defendant and a number of the other adolescent males, it was not likely that Defendant used force or coercion in his sexual encounters. The psychologist discerned a pattern involving all of these adolescents, including the victim, in which Defendant boldly touched the adolescent’s genitals; observed for reaction; progressed if the approach was accepted; and backed off if the approach was rejected.
At that hearing and following Dr. Dougher’s testimony, defense counsel withdrew his objection to the State’s calling the adolescent males as witnesses, because such testimony would provide essential background for Dr. Dougher’s opinion testimony. He indicated, however, that he would object to the State’s calling Defendant’s two sons because that testimony was highly prejudicial, confusing, and not relevant to any issues. The admissibility of the sons’ testimony will be discussed later.
We reject Defendant’s claim of ineffective assistance of counsel based on withdrawal of the objection. The withdrawal of the objection to the testimony was clearly a matter of tactics and strategy. As already noted, Defendant’s position at trial was that, although he did have a sexual relationship with the victim, it was entirely voluntary on the victim’s part. In presenting that position, Defendant relied on expert testimony about his condition of homosexual hebephilia, which causes him to be sexually attracted to male adolescents. Dr. Dougher testified that it was important for him, in forming an opinion about Defendant’s condition, to understand Defendant’s sexual history. He also stated that the testimony of the other adolescents who had been approached by Defendant was important in determining whether there was a consistent pattern in the way Defendant approached the adolescents. Finally, Dr. Dougher gave his opinion that Defendant’s claim of a noncoercive relationship with the victim was more consistent with Defendant’s condition than the victim’s claim of a coercive relationship. Thus, Defendant used the testimony of the adolescents to support the opinion of his expert witness which, in turn, bolstered his defense. The failure to object to this evidence, then, was a matter of trial tactics and strategy that we will not second-guess on appeal.1 See State v. Rodriguez, 107 N.M. 611, 615, 762 P.2d 898, 902 (Ct.App.) (ineffectiveness not necessarily established even when appellant establishes that trial counsel used improvident strategy or unsuccessful tactics), cert, denied, 107 N.M. 546, 761 P.2d 424 (1988).
c. Failing to Object to Allegedly Improper Closing Argument
Defendant claims failure of defense counsel to object to the use of prior misconduct in the State’s closing argument constituted ineffective assistance of counsel. While failure to object to improper closing argument may constitute ineffective assistance, because we find no reversible error in these comments, see point 3, it follows that trial counsel’s performance did not fall below the standards because he failed to object.
2. Trial Court Error
a. Amendment of Indictment and Denial of Continuance
The indictment alleged that the second series of incidents occurred “on or about” August 22. At trial, the victim testified, albeit ambiguously, that the incidents occurred on the Tuesday following the 18th, which would have been August 25. The State moved to amend the indictment to conform to the evidence. Defense counsel stated that there would be no objection, as long as Defendant was given an opportunity to investigate an alibi for August 25 and file a late notice of alibi if necessary. In response, the State argued that defense counsel’s investigator had been aware of the changed date for several months. Defendant then objected to the amendment. The judge allowed the amendment, and said he would take defense counsel’s request under advisement, and would not rule on it “at this time.” Defendant never renewed his request for more time to investigate an alibi.
The facts that the judge held his ruling in abeyance instead of denying Defendant’s request, and that Defendant never renewed his request, are fatal to Defendant’s position on this issue. A party must invoke a ruling from the trial court in order to preserve an issue for appeal; it is not enough to simply make a motion. See, e.g., State v. Cordova, 100 N.M. 643, 646, 674 P.2d 533, 536 (Ct.App.1983); State v. Andrada, 82 N.M. 543, 548, 484 P.2d 763, 768 (Ct.App.), cert. denied, 82 N.M. 534, 484 P.2d 754 (1971). Since Defendant did not renew his request for more time, the trial court may well have thought Defendant had been able to investigate his alibi thoroughly while this multi-day trial was continuing. It would therefore be inappropriate to hold that the trial court erred. Cf. State v. Garcia, 84 N.M. 519, 521, 505 P.2d 862, 864 (Ct.App.) (where trial court denied motion for severance, but left open possibility of severing at a later time if prejudice became apparent, and defendant did not renew his motion for severance, defendant waived the issue), cert. denied, 84 N.M. 512, 505 P.2d 855 (1972).
b. Incest Testimony by Defendant’s Son
As noted above, at the pretrial hearing on the motion in limine, Defendant withdrew his objection to the State calling other adolescents, but continued to object to the State presenting evidence of Defendant’s prior bad acts through Defendant’s sons. At trial, the prosecutor called only one of Defendant’s sons, Jeff. Jeff testified to incestuous conduct with Defendant that began when Jeff was eight years old and continued until he was fifteen. He said his father would crawl into bed and rub Jeff’s genitals under the covers. He also said that Defendant did the same thing to Jeff’s brother and that Jeff knew what was happening because he would hear his brother’s underwear “snap.” Jeff testified that Defendant also rubbed Jeff’s genitals in the shower, sometimes saying that he was giving Jeff a medical examination.
In objecting at the pretrial hearing, defense counsel urged that these acts were different from the relationships with the other adolescents; that their incestuous aspect made the acts different; that introducing evidence of them would create confusion; and that introducing evidence of them would compel the defense to go into Jeff’s mental health problems.
SCRA 1986, 11-404(B), states that:
Evidence of other crimes, wrongs or acts is not admissible to prove the character of a person in order to show that he acted in conformity therewith. It may, however, be admissible for other purposes, such as proof of motive, opportunity, intent, preparation, plan, knowledge, identity or absence of mistake or accident.
See State v. Lopez, 85 N.M. 742, 743-44, 516 P.2d 1125, 1126-27 (Ct.App.1973). At the pretrial hearing, the trial court overruled Defendant’s objection to the sons’ testimony, indicating that it was relevant and came within one or more of the exceptions, such as motive, opportunity, or intent. The court stated that there were similarities between Defendant’s activities with his sons and those alleged in the indictment, and that the evidence would be admitted.
We review the trial court’s actions for abuse of discretion. State v. McGhee, 103 N.M. 100, 104, 703 P.2d 877, 881 (1985). Applying that standard, we hold that the court did not abuse its discretion in allowing Jeff’s testimony at trial.
Even assuming that the testimony could be said to prove Defendant’s character or that he acted in conformity with this character,2 the evidence was not offered for that purpose. As previously discussed, the question of whether Defendant used his position of authority to coerce his victim was a critical issue in the case. Defendant argued at the pretrial hearing that the contacts with his sons were entirely different from those with the other adolescents. While there were some differences, certain similarities existed which made Defendant’s contacts with his sons highly relevant and within one or more of the exceptions to the rule.
It was important for the State that it prove Defendant used his position of authority to coerce his victim. “Position of authority” is defined as a “position occupied by a parent, relative, household member, teacher, employer or other person who, by reason of that position, is able to exercise undue influence over a child.” NMSA 1978, § 30-9-10(D) (Repl.Pamp.1984). “Undue influence” has been defined as “ ‘the result of moral, social, or domestic force exerted upon a party, so as to control the free action of his [or her] will----’” State v. Gillette, 102 N.M. 695, 702, 699 P.2d 626, 633 (Ct.App.1985) (quoting Trigg v. Trigg, 37 N.M. 296, 301, 22 P.2d 119, 123 (1933)). We agree with the trial court that the testimony of Defendant’s son was probative of the coercion issue.
The relevance and probative value of this testimony can be demonstrated by comparing Jeff’s testimony with that of one of the other adolescent victims, Terry. Terry testified that when he was thirteen or fourteen years of age, he went with Defendant’s family to their cabin in Ruidoso. This was in 1975 or 1976. After they arrived, Defendant grabbed Terry in the groin area as he walked through the kitchen in the cabin. That night Defendant got into bed with Terry and put his hand inside the boy’s underpants and attempted to masturbate him. Defendant then placed Terry’s hand inside Defendant’s pajamas and on Defendant’s penis. Terry struck Defendant and ran from the room.
The following day, Defendant again grabbed Terry’s groin. While driving back to Roswell, Defendant positioned the interi- or rear-view mirror so that he could look directly at Terry. Terry testified that Defendant gazed at him with an “evil look” which frightened and upset Terry.
Jeff testified similarly about Defendant’s mean nature and his fear of Defendant. Jeff was so afraid that, on cross-examination, when defense counsel asked whether Jeff .enjoyed his father’s sexual advances, Jeff testified that while he did not enjoy being touched, he enjoyed his father being nice to him, and that his father was nice on those occasions. At other times he was mean. Jeff said he was afraid of his father and could not look at him while on the witness stand. This type of control bore on the question of plan, design, and intent, as did Defendant’s attempt to control Terry, and was relevant to counter Defendant’s contention that the relationship between Defendant and the victim was consensual.
While the contacts in question were with Defendant’s sons, which made them different from those with the other boys, the use of control and the approach were similar.
The result we reach is consistent with State v. Lucero, 114 N.M. 489, 840 P.2d 1255 (App.1992). In the case before us, Jeff’s testimony went directly to the question of whether Defendant had the plan, design, or intent to control the victim by use of position of authority. Jeff was an adolescent male when Defendant molested him, as was the victim, and Defendant used his position of authority as a father to attain his ends with Jeff, just as he used his position of authority as a supervisor to attain his ends with the victim. In Lucero, however, the evidence presented was so factually dissimilar to the alleged acts giving rise to the charges that it simply was not probative of plan, design, or intent. The Lucero Court flatly rejected the “State’s assertion that occasional rejection of Defendant’s request for oral sex by his girlfriend is admissible to prove he sexually assaulted the seven-year-old daughter of a friend.” Id. at 493, 840 P.2d at 1259. The factual differences between one act, arguing with an age-appropriate girlfriend about sex, and the other, sexually molesting a seven-year-old girl, simply were too great for the former to be admissible under Rule 11-404(B) to show that the defendant had the plan, design, or intent to commit the latter.
Additionally, SCRA 1986, 11-404(A)(1), permits evidence of a pertinent character trait when offered by an accused, or by the prosecution in rebuttal. As discussed earlier, the defense’s theory was based on propensity. Defendant’s expert testified that in his opinion Defendant did not use his position of authority or other types of coercion to get his way with boys. Jeff’s testimony contradicted that theory. While that testimony was offered as part of the State’s case, given the fact that the defense made its theory known as early as the pretrial hearing, the State could have anticipated this theory and offered rebuttal testimony before Defendant put on his case.
In balancing the probative value of evidence with its prejudicial effect, it ordinarily would be difficult to imagine anything more prejudicial than evidence of incest. Viewing the trial in its entirety, however, we believe that the testimony in question lost much of its sting. As already noted, the defense strategy was to present an open, unabashed disclosure of Defendant’s sickness and to persuade the jury that the relationships were consensual, not coercive. That strategy brought before the jury a series of witnesses who depicted, in graphic detail, Defendant’s activities, including meeting men in gay bars, hustling boys off the street, and frequenting adult video parlors. We believe the jury was so inoculated to such sordid testimony, the trial court could find that the evidence of incestuous activities added little prejudicial effect to what had already been presented.
Therefore, we find no abuse of discretion in allowing this testimony under the unusual circumstances of this case.
3. Closing Argument
Defendant claims that the prosecutor engaged in an unfair closing argument that amounted to fundamental error. Since there was no objection, Defendant must rely on fundamental error. See SCRA 1986, 12-216 (Repl.1992).
Defendant describes comments made by the prosecutor about Defendant’s sickness, his hustling boys, and his activities in video parlors. These statements are based on the evidence. Comments on the evidence are not error or fundamental error. See State v. Taylor, 104 N.M. 88, 94, 717 P.2d 64, 70 (Ct.App.) (prosecution allowed reasonable latitude in closing argument, but remarks must be based on the evidence presented), cert. denied, 103 N.M. 798, 715 P.2d 71 (1986).
Nor do we find any error in the prosecutor’s favorable comments about defense counsel, and Defendant has not provided argument or authority why this comment constitutes fundamental error. See In re Adoption of Doe, 100 N.M. 764, 765, 676 P.2d 1329, 1330 (1984) (appellant must present argument and authority on each appellate issue).
Finally, Defendant argues that the prosecutor expressed his personal opinion or belief as to Defendant’s guilt or the credibility of witnesses. While it is correct that a prosecutor is prohibited from expressing his or her personal view on these matters, see State v. Ferguson, 111 N.M. 191, 194, 803 P.2d 676, 679 (Ct.App.), cert. denied, 111 N.M. 144, 802 P.2d 1290 (1990), we believe the comments in question did not clearly violate that principle. We are not persuaded by the State’s concession that the remarks were improper.3
The prosecutor’s comment that “I think this [case] has the facts necessary for you to convict the accused,” could be viewed as proper. See Id. at 195, 803 P.2d at 680 (quoting from F. Bailey & E.H. Rothblatt, Successful Techniques for Criminal Trials 25:16, at 565-66 (2d ed. 1985)). “ ‘The right of a prosecuting attorney to draw in his argument all legitimate inferences from the evidence authorizes him to assert a belief based on the evidence that the accused is guilty.’ ” Id.
Similarly, the comment about the State’s burden of proving coercive use of authority and the prosecutor’s belief that Defendant was in a position of authority could be viewed as drawing on the evidence. While the prosecutor should not have prefaced his remark about the statements of Garth Dennis, with whom the victim had a relationship, with “I think,” we are not persuaded that the jury would necessarily have considered the remark personal rather than something established by the evidence and inferences.
We will not find fundamental error in an ambiguous comment when a timely objection would have afforded the court and the prosecutor an opportunity to cure any problem by resolving the ambiguity.
4. Loss of Exhibits
Defendant claims he was prejudiced by the loss of two photographs that were introduced into evidence. However, he does not explain how he was prejudiced. See State v. Hoxsie, 101 N.M. 7, 10, 677 P.2d 620, 628 (1984) (an assertion of prejudice is not a showing of prejudice), overruled on other grounds by Gallegos v. Citizens Ins. Agency, 108 N.M. 722, 731, 779 P.2d 99, 110 (1989).
Defendant relies on State v. Chouinard, 96 N.M. 658, 634 P.2d 680 (1981), cert. denied, 456 U.S. 930, 102 S.Ct. 1980, 72 L.Ed.2d 447 (1982). Defendant’s reliance is misplaced. Chouinard involved the destruction of evidence before trial. Here, we are dealing with two photographs, both of which were apparently admitted into evidence and presumably published to the jury. Thus, Defendant was not deprived of the opportunity to have the jury consider these photographs, even if the jury was unable to take them to the jury room during the deliberations. The loss of the exhibits does not require reversal.
5. Cumulative Error
Having found that no error occurred, we reject this claim. See State v. Isiah, 109 N.M. 21, 32, 781 P.2d 293, 304 (1989) (where there has been no accumulation of irregularities at trial, cumulative error does not exist).
We affirm Defendant’s convictions.
IT IS SO ORDERED.
DONNELLY, J., concurs. HARTZ, J., specially concurs.