DISSENT
ANDERSON, Paul H., Justice(dissenting).
I respectfully dissent. The confluence of three key factors in this case leads me to conclude that the defendant Donald Warren Hayes did not get a fair trial. The three factors are: (1) the nature, content, and thrust of the medical examiner’s testimony, (2) the State’s willingness to compound the potential harm from the medical examiner’s testimony by employing suggestions, innuendos, and insinuations, and (3) the fact that our standard of review for claims of insufficient evidence once again magnifies the importance of a medical examiner’s testimony and the potential for permanent harm when the State uses such testimony to obtain an otherwise uncertain conviction.
At first glance, none of these three factors standing alone may appear to create a situation sufficient to warrant reversal and a new trial — but, when scrutinized together, they do just that. The confluence of these factors has created a situation in which it is difficult, if not impossible, for me to conclude that the defendant received a fair trial. Moreover, the errors that deprived the defendant of a fair trial were not harmless beyond a reasonable doubt— there simply is not enough evidence in this record to convince me beyond a reasonable doubt that the error did not have a significant impact on the jury’s verdict of guilty. Therefore, I dissent. I would reverse and remand for a new trial.
The facts of this case are tragic. A little child, 13-month-old Robert, is dead. The medical examiner testified that “Robert died of complications of blunt force cranio-cerebral injuries.” In more understandable terms, Robert died as the result of brain injuries marked by a large star-shaped fracture centered on the back of his skull. There is evidence that Robert’s life shortly before and at the time of his death was filled with physical trauma. A post-death medical examination revealed evidence of four other bruises to Robert’s head; two fractures in his left arm, one of which had gone untreated; rib fractures; extensive hemorrhaging in his eyes; and a tissue tear in his mouth. It is definitely not normal for a child to have this many injuries — especially of this type and magnitude.
Robert suffered the fatal brain injury while in the care of the defendant, Donald Warren Hayes. Hayes is an unsympathetic defendant and, not surprisingly, his character and past behavior became a major issue in this case. At the time of Robert’s death, Hayes was involved in a romantic relationship with Robert’s mother, T.D. Around July 2008, Hayes moved in with T.D. and T.D.’s four children, 10-year-old D.H., 6-year-old M.H., 2-year-old C.A., and the infant Robert. Hayes was unemployed at the time, so when T.D. was working 25 to 30 hours per week at a local fast-food restaurant, Hayes looked after her children — for about 90 percent of that time.
The evidence shows that Hayes joining T.D.’s household was not a positive turn of events for T.D.’s children. Friends who knew the children testified that the children were happy before Hayes moved in, but after he moved in the children were *558“scared” and “weren’t happy.” The record shows that the children suffered physical abuse while Hayes was in the home, but there was no evidence directly linking Hayes to injuries that would be classified as abuse. There is also evidence that Hayes physically abused a woman with whom he had an on-and-off romantic relationship between 2000 and 2006.
But the question before us is not whether Hayes is a good person — the record indicates that he falls short of being a model citizen. The key question is not whether Hayes’s past behavior shows that he is capable of hurting other people. The question before us is whether the State has proven beyond a reasonable doubt that on the afternoon of September 24, 2008, Hayes committed first-degree domestic abuse murder resulting in the death of 13-month-old Robert. The answer to that question is not so clear, and I will explain why I have come to this conclusion.
The Medical Examiner’s Testimony
While there is evidence in the record that Robert was the subject of prior abuse, the evidence that Robert was murdered by Hayes on September 24, 2008, as opposed to being the victim of an accident, was circumstantial and hotly contested. In this context, the weight of the medical examiner’s forensic testimony and conclusion as to the cause of Robert’s death is highly significant.
When we apply our standard of review to the facts of the case before us today, I am concerned that our application of that standard has led us to improperly affirm Hayes’s conviction. Here, the medical examiner’s testimony came close to invading — or even did invade — the province of the jury. In his testimony at trial, the medical examiner rendered the ultimate conclusion that 13-month-old Robert’s death was the result of a homicide committed by Hayes. Upon rendering this conclusion, the medical examiner not only implied that Hayes was guilty of the crime as charged, but provided testimony that directly refuted Hayes’s claim that the cause of death was an accidental injury. It refuted Hayes’s defense that he tripped on a fan cord while carrying Robert, causing both Hayes and Robert to fall and hit the floor. It also rejected the testimony of Robert’s sister, M.H. M.H. testified that Hayes heard Robert cry again and while displaying a “mad face” Hayes “went back in [the bedroom] and grabbed [Robert] and then [Hayes] didn’t see the fan cord and he tripped and fell right on top of [Robert].”
At this point, it is prudent to review what the medical examiner told the jury. The medical examiner said that the manner of death was homicide, that many of Robert’s injuries were “suspicious,” and that a trip and fall of the type described by Hayes and M.H. could not account for the injuries that caused Robert’s death. The medical examiner testified that Robert’s injuries were too severe to be the result of a typical household fall — an opinion that was shared by two other physicians and a nurse, all of whom treated Robert. Such testimony is within the medical examiner’s expertise, but the medical examiner’s testimony was also supplemented with multiple references to Robert’s prior injuries. It is within the ambit of this part of the medical examiner’s testimony where the problems reside. The medical examiner repeatedly used these earlier injuries, none of which was directly linked to Hayes, and others which clearly had other causes, as the basis for his testimony that the fall Hayes described was not the ultimate cause of Robert’s death. I conclude that the testimony that followed from this conclusion may have invaded the decision-making process of the jury.
*559Here are some of the relevant parts of the medical examiner’s testimony:
Q. And what was essentially the short version of what you understand Mr. Hayes’s explanation to be for Robert’s injury on the 24th of September?
A. My understanding would be that Mr. Hayes was carrying Robert. Mr. Hayes tripped over a fan causing him to fall and drop Robert on, as I recall, he specifically stated that he did not land on top of Robert.
Q. Did that explanation account for the death of Robert as you determined it to have been caused?
A. No I don’t believe it does.
Q. Why is that doctor?
A. Ah well there’s a couple of reasons for that. One reason is that Robert has more than one braise on his head and so — and we’ll show you pictures of this later but basically he’s got multiple impact sites on his scalp, not just one. The nature of Robert’s skull fracture is far in excess of my understanding of what infants would usually sustain from a — from a simple indoor fall. And — and again, I’ll show you a picture of Robert’s skull fracture to explain just what I mean by the term far in excess of — um and the other thing that’s very disconcerting about Robert’s case is that he was found to have a broken arm that ivas healing at the time he presented with his head injury unbeknownst to the clinicians but discovered at autopsy, Robert also had four healing rib fractures when I examined him at autopsy. The rib fractures would be very difficult um to explain by a fall. You know, barring a very unusual prior accident, intentional injury to Robert’s rib cage would be the only explanation for those as well. So when I take a child with a head injury like Robert’s in the context of other very suspicious injuries, it’s very difficult for me to — to accept that as being from a trip and fall....
Q. Now in this case doctor, you had information that the defendant had said that he had tripped and fallen with Robert in his arms and that Robert apparently had then landed some six or eight feet from him hitting the wooden floor and then started breathing funny. Do you— do you recall that?
A. Yes.
Q. And why is it that you don’t think that fall accounts for Robert’s ultimate death?
A. Well, there’s a couple of reasons for that. First is the death from a head injury due to an indoor fall in an infant would be a very, very unusual event to begin with. In Robert’s case, I also have to deal with the fact that his skull fracture is not a relatively simple or linear fracture. It’s actually a fairly large fracture that is stellate that crosses suture lines and Robert obviously has a devastating life threatening brain injury concomitant with that fracture. Um then I have to put that in the context of this is a child who has a broken arm that’s untreated and we go on to discover four ribs that are fractured in a place that really, in a circumstance like this, abuse is about the only legitimate reason that you would have those rib fractures. So when I take all of those things together, to me, the only logical conclusion is *560that history is not telling you what really happened.
(Emphasis added).
Later, during direct examination by the State, Robert’s sister, M.H., provided direct testimony that contradicted the medical examiner as to the cause of death when she described witnessing Hayes trip over the fan cord and fall when he was carrying Robert. M.H.’s testimony is as follows:
Q. [M.H.], do you remember the day that your brother got taken in the ambulance to the hospital?
A. Yes.
Q. Were you home before that?
A. Yes.
Q. And did you go to school that day?
A. Yes.
Q. What happened once you got home from school?
A. Um Robert was crying and [Hayes] kept on swearing at him. He said the “b” word and the “f” word to him and — and put him in his crib and — and then he started crying and [Hayes] went back in and grabbed him and then he didn’t see the fan cord and he tripped and fell right on top of him.
M.H.’s testimony was in part corroborated by Robert’s brother, D.H. D.H. testified that when he got home from school, Robert was fine and while D.H. was in his bedroom doing homework he heard the sound of “a little crash” that sounded “[l]ike books falling.”
Hayes also presented testimony from a medical doctor, with 30 years of experience as a forensic pathologist, that Robert’s head injuries were consistent with Hayes’s description of a trip and fall. The physician explained how “Newtonian mechanics” (“the study of motion”) and biomechanics (“the application of the principles of mechanics to living tissues”) can be used to quantify the amount of force necessary to account for the head injuries that Robert sustained. The physician described several studies that have applied the principles of Newtonian mechanics to injury evaluation. The physician then explained how he used the knowledge gained from the data generated in these studies to quantify the amount of force necessary to cause the injuries Robert sustained and to reach the conclusion that the injuries were consistent with Hayes’s tripping and falling. The physician went on to testify that there is no way to evaluate the likelihood of Robert’s injuries having been inflicted accidentally versus intentionally because the act of walking, tripping, and falling with Robert is a mechanically equivalent event to the act of throwing him into a wall. While medical opinions can legitimately vary, the testimony of the defendant’s physician raises question regarding the medical examiner’s certitude as to the ultimate question here: What and who, if anyone, caused Robert’s death?
We have repeatedly expressed both caution and concern about expert opinions that embrace legal conclusions and invade the province of the jury. Our rules of evidence only permit expert opinion testimony if such testimony is helpful to the factfinder. We engaged in an extensive discussion of our view on the proper role of expert testimony in State v. Moore, 699 N.W.2d 733 (Minn.2005). In that case, we said:
Because an expert with special knowledge has the potential to unduly influence a jury ... “[s]pecial care must be taken by the trial judge to ensure that the defendant’s presumption of innocence does not get lost in the flurry of expert testimony and, more importantly, that the responsibility for judging credibility and the facts remains with the jury.”
*561Id. at 739-40 (quoting State v. Greeinger, 569 N.W.2d 189, 193 (Minn.1997)). We have also said:
Expert opinion' testimony is not helpful if “the subject of the testimony is within the knowledge and experience of a lay jury and the testimony of the expert will not add precision or depth to the jury’s ability to reach conclusions about that subject which is within their experience.” State v. Helterbridle, 301 N.W.2d 545, 547 (Minn.1980).
Id. at 740 (quoting State v. Helterbridle, 301 N.W.2d 545, 547 (Minn.1980)).
Under our helpfulness test, we generally do not allow ultimate issue testimony. We have been very explicit on this point. We have said:
Under the helpfulness test, this court “has not allowed ultimate conclusion testimony which embraces legal conclusions or terms of art.” In addition, this court has stated that “[wjhile the evidentiary rules do not bar all expert testimony concerning the ultimate issue, a district court may exclude ultimate issue testimony ... when the testimony would merely tell the jury what result to reach.”
Id. (citations omitted).
What we said in Moore for the most part echoed what we had said more than 20 years earlier in State v. Saldana, 324 N.W.2d 227 (Minn.1982). We stated that expert testimony is only admissible if it is helpful to the jury. We explained:
If the subject of the testimony is within the knowledge and experience of a lay jury and the testimony of the expert will not add precision or depth to the jury’s ability to reach conclusions about that subject which is within their experience, then the testimony does not meet the helpfulness test.
Id. at 229 (quoting Helterbridle, 301 N.W.2d at 547). We concluded:
If the jury is in as good a position to reach a decision as the expert, expert testimony would be of little assistance to the jury and should not be admitted. Expert testimony may also be excluded if its probative value is substantially outweighed by the danger of unfair prejudice, confusion, or misleading the jury. Minn. R. Evid. 403. Under this test of admissibility, we must examine each segment of [an expert’s] testimony.
Id. (citation omitted). Later in Saldana, we added the following observation:
The primary criterion for admissibility is the helpfulness requirement as discussed above. An expert witness may testify in the form of an opinion, Minn. R. Evid. 702, and opinion testimony is not objectionable merely because it embraces an ultimate issue to be decided by the jury, Minn. R. Evid. 704. However, according to the Advisory Committee Comment to Rule 704, opinions involving a legal analysis or mixed questions of law and fact are deemed to be of no use to the jury.
Id. at 230.
What concerns me most about the medical examiner’s testimony is that he took his analysis of the injuries that he concluded were the immediate cause of Robert’s death, tightly tethered those injuries to Robert’s prior injuries, and then linked the prior injuries to the fatal injury in order to opine that Hayes killed Robert in some manner other than an accidental fall. The medical examiner then asserted that a fall as described by Hayes and M.H. could not have been the cause of the injuries that killed Robert. The State took this testimony and used it to speculate that Hayes “slammed Robert’s head into a hard surface.” The State presented this speculation to the jury even though a thorough *562search of T.D.’s entire residence by the Bureau of Criminal Apprehension revealed no forensic evidence to support it. While the foregoing, conclusion by the medical examiner could have been reached by the jury when rendering a verdict, it was not an opinion the medical examiner should have been permitted to convey. In essence, the medical examiner’s opinion invaded the legitimate realm of the jury as the factfinder.
The Role of the Medical Examiner
We expect independence, autonomy, and neutrality from our medical examiners. Medical examiners are state actors in the criminal justice system who have a very key role to play. We have said that medical examiners theoretically enjoy autonomy from those government officials directly responsible for investigating and prosecuting crimes. See State v. Beecroft, 813 N.W.2d 814, 833 (Minn.2012). By statute, a “medical examiner is an independent official of the county, subject only to appointment, removal, and budgeting by the county board.” Minn.Stat. § 390.011 (2012) (emphasis added). Thus, similar to a traditional coroner who occasionally worked alongside the county sheriff but also acted as a check on the sheriffs power, a medical examiner may from time to time assist law enforcement by conducting honest and objective death investigations, but must at all times remain a neutral participant in our criminal justice system.
It is “undisputed that the quality of forensic investigation improves when medical examiners operate free from the influence of law enforcement and prosecutors.” Beecroft, 813 N.W.2d at 833 (citing Nat’l Research Council of Nat’l Acads., Strengthening Forensic Science in the United States: A Path Forward 23-24 (National Academies Press 2009)). The National Association of Medical Examiners (“NAME”) proclaims in its standards for medicolegal death investigations “that independence from law enforcement agencies and prosecutors ‘promotes neutral and objective medical assessment of the cause and manner of death.’ ” Id. at 833-34 (quoting Garry F. Peterson & Steven C. Clark, Nat’l Assoc. of Med. Standards, Forensic Autopsy Performance Standards 7 (2011)). Accordingly, “most medical examiners ‘view themselves first and foremost as scientists, beholden not to one side or the other, but only to the truth.’” Id. at 883 (quoting Mark Hansen, CSI Breakdown, A.B.A. J., Nov. 2010, at 44, 46). Stated differently, a medical examiner’s primary purpose is not to solve crimes but to serve the public by determining how people die. See, e.g., United States v. Rosa, 11 F.3d 315, 332 (2d Cir.1993). In Rosa, the Second Circuit said:
[Aljthough law enforcement activities are typically accusatory and adversarial in nature, a medical examiner’s reported observations as to a body’s condition are normally made as part of an independent effort to determine a cause of death. Indeed, a medical examiner, although often called a forensic expert, bears more similarity to a treating physician than he does to one who is merely rendering an opinion for use in the trial of a case.
Id. (citation omitted) (internal quotation mark's omitted); see also People v. Washington, 86 N.Y.2d 189, 630 N.Y.S.2d 693, 654 N.E.2d 967, 969 (1995) (explaining that a medical examiner’s mandate “is clear, to provide an impartial determination of the cause of death”). It is unfortunate that “[sjome police and prosecutors tend to view government-employed forensic scientists, including medical examiners, not as independent experts, but as members of the prosecution’s ‘team.’ ” Beecroft, 813 *563N.W.2d at 834 (quoting Hansen, supra, at 46).
It is important to keep in mind that, as physicians, medical examiners are forensic scientists and as such they are treated as expert witnesses. Their testimony carries much weight in a courtroom. If anyone has any doubts on this point, all they have to do is ask a trial attorney about the CSI effect on jurors. See Andrew P. Thomas, The CSI Effect: Fact or Fiction, 115 Yale L.J. Pocket Part 70, 70-72 (2006) (surveying experienced prosecutors with trial experience about the CSI effect on jurors). But forensic scientists, like everyone else, do make mistakes. Beecroft, 813 N.W.2d at 835-36. That is why we must put in place systems and procedures that make sure the work product and the nature and scope of forensic experts like medical examiners will be properly framed and scrutinized. Because the opinions of experts like medical examiners are so highly valued and have such an impact in the courtroom, we must hold their opinions to the highest standards so that mistakes are not made.
Because forensic science testimony in general, and medical examiner forensic testimony in particular, typically carries such great weight, there is considerable potential for such testimony to mislead a jury if not carefully scrutinized. While we expect “independence, autonomy, and neutrality” from a medical examiner, we do not always receive it. See generally Beecroft, 813 N.W.2d at 831-36. This is why both defense counsel and the court must monitor the nature and content of this testimony. We noted this need when we said that:
Justice Harry Blackmun recognized that jurors “tend to assume [scientific evidence] is more accurate and objective than lay testimony.” Consequently, “[t]he major danger of scientific evidence is its potential to mislead the jury” because “an aura of scientific infallibility may shroud the evidence and thus lead the jury to accept it without critical scrutiny.”
Id. at 839 n. 14 (citations omitted). The nature of the medical examiner’s testimony at Hayes’s trial, when combined with how the State used that testimony, is at the heart of what concerns me about this case.
The State’s Closing Argument
The problems with the medical examiner’s testimony were exacerbated when the State, in its closing argument, emphasized over and over again the other injuries suffered by T.D.’s children, many of which were not linked or attributed to Hayes. The State repeatedly referenced the children’s injuries and maladies, creating the implication for the jury that Hayes caused them. There were several references by the State to injuries to the children that had no explanation or testimony linking them to Hayes.
The State’s final argument contains an inordinate amount of inflated rhetoric. It is laden with suggestions, innuendos, and insinuations. Examples include using the term “child molester” in connection with Hayes when he was never so much as accused of such a crime, and implying that Hayes was connected to several injuries to Robert that the State knew he did not cause. It contained many statements that were unfounded, with no support in the trial record. There was a specific implication that stomach cramping and constipation problems experienced by one of the children were caused by Hayes, despite the fact that there was nothing in the record linking Hayes to the child’s malady. The argument even contained an implicit suggestion that if circumstances had been different, one of the witnesses would not be alive today because Hayes would have *564killp.rl her. The closing statement was also filled with dismissive and derisive comments about Hayes’s parenting skills — including rhetorical statements bordering on sarcasm. After reviewing the closing argument, I am left with the impression that the State improperly based its argument on the premise that the jury should convict Hayes because he is a bad person. While Hayes may in many respects be a bad person, that is not a proper basis upon which to convict him of first-degree murder.1
Impartiality is more than just a goal for every person who represents the sovereign — it is a duty. Improper suggestions, innuendos, and insinuations have no place in a prosecutor’s tool box. A prosecutor who represents the government is a minister of justice. The Supreme Court and our court have made this point on so many occasions that they need not be cited. A good example appears in Berger v. United States where the Supreme Court said that a prosecutor:
is the representative not of an ordinary party to a controversy, but of a sovereignty whose obligation to govern impartially is as compelling as its obligation to govern at all; and whose interest, therefore, in a criminal prosecution is not that it shall win a case, but that justice shall be done. As such, he is in a peculiar and very definite sense the servant of the law, the twofold aim of which is that guilt shall not escape or innocence suffer. He may prosecute with earnestness and vigor — indeed, he should do so. But, while he may strike hard blows, he is not at liberty to strike foul ones. It is as much his duty to refrain from improper methods calculated to produce a wrongful conviction as it is to use every legitimate means to bring about a just one.
It is fair to say that the average jury, in a greater or less degree, has confidence that these obligations, which so plainly rest upon the prosecuting attorney, will be faithfully observed. Consequently, improper suggestions, insinuations, and, especially, assertions of personal knowledge are apt to carry much weight against the accused when they should properly carry none.
295 U.S. 78, 88, 55 S.Ct. 629, 79 L.Ed. 1314 (1935) (emphasis added).
Standard of Review
Even if improper forensic testimony does not sway a jury, it can still have a powerful, illegitimate effect on the outcome of a criminal prosecution. When appellate courts in Minnesota review the sufficiency of the evidence leading to a conviction, “we view the evidence in the light most favorable to the verdict and assume that the factfinder disbelieved any testimony conflicting with that verdict.” State v. Holliday, 745 N.W.2d 556, 562 (Minn.2008) (citation omitted) (internal quotation marks omitted). When we apply this standard of review to cases where the conviction is based on an expert’s forensic evidence, the harm that can result should the forensic witness exceed the bounds of his or her scientific expertise can be magnified. Because we entrust medical examiners with such great power, we must — and do — demand that they exercise that power with the utmost care, impartiality, and integrity. The bottom line for the foregoing scenario is that when we apply our standard of review in a case like the one before us today— where there is a confluence of multiple *565factors that are at best on the edge of error — there is an enhanced possibility that errors may pass by us uncorrected.
When all is said and done with respect to the case before us, it is difficult to point to one specific act or factor that constitutes clear error. Did the medical examiner just play it close to the line or did he step over the line? Did the State in its prosecution of this case willingly exacerbate the problems we now face by deliberately making an attempt to expand the scope of the medical examiner’s testimony? Were the numerous suggestions, innuendos, and insinuations made by the State in its closing argument the legitimate pursuit of justice “with earnestness and vigor?” Berger, 295 U.S. at 88, 55 S.Ct. 629. Was the State merely striking “hard blows?” Id. On the other hand, was the State striking “foul ones” by using “improper methods calculated to produce a wrongful conviction?” Id. I concede that discerning the correct answers to these questions is difficult and open to legitimate debate, and may result in differing conclusions. What I can say for certain is that in this tragic and difficult case, I am not left with a clear and strong conviction that there was no error or that any error was harmless beyond a reasonable doubt. Therefore, I would reverse and remand for a new trial so that we can be assured that “justice shall be done.” Id.
. I have included in an attached appendix several of the actual statements made by the State so that the reader can render his or her own judgment as to the nature of the arguments made by the State.