(concurring).
I cannot disagree with the opinion of the court that, under existing law regarding Minn.Stat. § 544.42, subd. 6(c) (2014), as applied to the parties’ arguments in this particular case of alleged legal malpractice, we must reverse the court of appeals. I write separately to suggest that the controlling case, Brown-Wilbert, Inc. v. Copeland Buhl & Co., 732 N.W.2d 209 (Minn. 2007), both fundamentally misreads the statute and conflicts with our more recent medical malpractice precedent. Brown-Wilbert should be revisited and its key holding overruled.
I.
The court correctly accepts Guzick’s interrogatory answer incorporating the expert review affidavit as the expert disclosure affidavit required by section 544.42, subdivision 6(c). The court then accurately articulates the test for whether expert testimony is required: “whether a plaintiff is required to make an expert disclosure is something that must be determined on a case-by-case basis for each element of the prima facie case of malpractice.” Expert testimony is generally required on the elements of the standard of care and its breach. Wartnick v. Moss & Barnett, 490 N.W.2d 108, 116 (Minn.1992). As the court notes, we have not necessarily required expert testimony to establish the attorney-client relationship and but-for causation.
The remaining element of malpractice is proximate cause. As the court indicates, Kimball agrees with the court of appeals that, in this legal malpractice case, an expert was required to establish proximate causation and, interestingly, Guzick does not disagree. Had he done so, it would, have been a close call as to whether an expert was necessary to establish proximate cause under the facts of this case.1
Given Guzick’s concession, the court does not err in considering his expert disclosure to be “conclusory.” If an expert disclosure is only “conclusory,” then, pursuant to Brown-Wilbert, it does not qualify for the safe harbor of section 544.42, subdivision 6(c), discussed below. Thus, given the particular posture of this case, and applying the existing precedent under the applicable statute, it follows that the court of appeals must be reversed and Kimball must be granted summary judgment.
*53II.
While I concur, reluctantly, in this result, I hope that soon we will have an opportunity to revisit Brown-Wilbert. While neither party urged us to overrule it, the holding of Brovm-Wilbert conflicts with both the plain language of section 544.42 and our later interpretation of the substantively similar medical malpractice statute.
I read section 544.42, the statute governing expert disclosures in malpractice cases against lawyers, accountants, and design professionals, as clear and unambiguous. Under the statute, a plaintiff must serve an expert disclosure — containing an expert’s opinion, if necessary, establishing the elements of the prima facie case— within 180 days after commencement of discovery. Minn.Stat. § 544.42, subds. 2(2), 4(a) (2014). If the plaintiff fails to “comply with subdivision 4,” the defendant may move the district court for “mandatory dismissal of each action with prejudice as to which expert testimony is necessary to establish a prima facie ease.” Minn. Stat. § 544.42, subd. 6(c). • But such a motion “based upon claimed deficiencies of the affidavit or answers to interrogatories shall not be granted” unless the district court provides: (1) notice containing “specific findings as to the deficiencies of the affidavit or answers to interrogatories; and (2) 60 days to “satisfy the disclosure requirements in subdivision 4.” Minn.Stat. § 544.42, subd. 6(c) (emphasis added). The 60 days to cure the deficiencies is the so-called “safe harbor.”
Here, Guzick submitted as his expert disclosure an answer to an interrogatory incorporating the expert review affidavit in which the expert opined that ten different acts were negligent. Upon the motion to dismiss by Kimball, the statute required the district court to provide notice to Guz-ick identifying any deficiencies in his disclosure — such as, in this case, a condusory statement on proximate causation — and allow 60 days for Guzick to cure the deficiencies. Thus, when the district court granted Kimball’s motion to dismiss without allowing safe harbor, it did not follow the plain language of the statute.
But I cannot fault the district court because it relied — as the court does today— on Brovmr-Wilbert to deny access to the safe harbor. In Brown-Wilbert, our court, in a 5-2 decision, held that plaintiffs must provide a “meaningful disclosure” in order to qualify for the safe harbor. 732 N.W.2d at 219. The Brovm-Wilbert majority reasoned that only disclosures containing “minor deficiencies” would be allowed safe harbor; those with major deficiencies would have no such opportunity, as “[a]ny other interpretation would render the 180-day requirement meaningless.” Id. at 217-18. This “meaningful disclosure” standard adopted by Brovm-Wilbert and applied today is erroneous, and should be abandoned so. that we can return to the statute’s plain language.
The “meaningful disclosure” standard, and the related concepts of “major” and “minor” deficiencies, are judicial concoctions. The statute does not use the phrase “meaningful disclosure,” and nothing in the statute states or implies that only affidavits with “minor” deficiencies qualify for safe-harbor protection. Rather, the statute says clearly that any deficient affidavit or interrogatory answer qualifies for the safe harbor.2 See Minn.Stat. § 544.42, *54subd. 6(c). Brown-Wilbert added words to an unambiguous statute, in conflict with the direct instruction from the Legislature on how to interpret its laws: “When the words of a law in their application to an existing situation are clear and free from all ambiguity, the letter of the law shall not be disregarded under the pretext of pursuing the spirit.” Minn.Stat. § 645.16 (2014); see also Cty. of Dakota v. Cameron, 839 N.W.2d 700, 709 (Minn.2013) (“[W]e do not add words or phrases to an unambiguous statute.”).3
Further, the precedent invoked by Brown-Wilbert does not prop up its house of cards. Brown-Wilbert cited four medical malpractice cases that espoused some variation of the “meaningful disclosure” standard. 732 N.W.2d at 217; see also Teffeteller v. Univ. of Minn., 645 N.W.2d 420, 430 (Minn.2002) (requiring the affidavit to provide “more than a sneak preview”); Lindberg v. Health Partners, Inc., 599 N.W.2d 572, 578 (Minn.1999) (requiring more information than simply identification of the expert or a “general disclosure”); Stroud v. Hennepin Cty. Med. Ctr., 556 N.W.2d 552, 555 (Minn.1996) (requiring the affidavit to do more than “simply repeat facts in the hospital or clinic record”); Sorenson v. St. Paul Ramsey Med. Ctr., 457 N.W.2d 188, 193 (Minn. 1990) (disapproving of “empty conclusions which, unless shown how they follow from the facts, can mask a frivolous claim”). While Brown-Wilbert conceded that applying these medical malpractice cases to the non-medical professional malpractice statute was of limited value, 732 N.W.2d at 217, it did so anyway by applying Soren-son ⅛ “meaningful disclosure” standard to deny the plaintiff access to the safe harbor. See Brown-Wilbert, 732 N.W.2d at 219 (quoting Sorenson, 457 N.W.2d at 193).
But the medical malpractice cases cited by Brown-Wilbert had no real value, as the medical malpractice statute did not even contain a safe harbor at the time. See Act of May 22, 2002, ch. 403, § 1, 2002 Minn. Laws , 1706, 1706-07 (codified as amended at Minn.Stat. § 145.682, subd. 6(c) (2014)) (amending the medical malpractice statute to add a safe harbor). Indeed, in the absence of a statutory safe harbor, the “meaningful disclosure” standard was actually a judicially-created safe harbor, giving “borderline” plaintiffs— those with minor deficiencies — “less drastic alternatives to a procedural dismissal.”4 Sorenson, 457 N.W.2d at 193; see also Wesely v. Flor, 806 N.W.2d 36, 40 (Minn.2011).
Perceiving that this judicial safe harbor was inadequate, the Legislature enacted a statutory safe harbor for medical malpractice cases. See Wesely, 806 N.W.2d at 40. Now a failure to comply with the expert disclosure requirement results, upon motion, in:
*55[Mandatory dismissal with prejudice of each action as to which expert testimony is necessary to establish a prima facie case, provided that: (1) the motion to dismiss the action identifies the claimed deficiencies in the affidavit or answers to interrogatories; (2) the time for hearing the motion is at least 45 days from the date of service of the motion; and (3) before the hearing on the motion, the plaintiff does not serve upon the defendant an amended affidavit or answers to interrogatories that correct the claimed deficiencies.
Minn.Stat. § 145.682, subd. 6(c) (2014). This medical malpractice safe harbor is substantively the same as the non-medical professional malpractice safe harbor found in section 544.42, subdivision 6(c).
In Wesely v. Flor, 806 N.W.2d 36, 41-43 (Minn.2011), decided four years after Brown-Wilbert, we interpreted the medical malpractice safe harbor. Unlike in Brown-Wilbert, a 6-0 majority5 read the statute literally. “The statute plainly states that the safe-harbor period applies every time the defendant moves to dismiss under Minn.Stat. § 145.682, subd. 6. The statute does not limit the safe-harbor period to only certain types of deficiencies.” Wesely, 806 N.W.2d at 41 (emphasis added). Thus, in applying the plain language of the medical malpractice safe harbor, we expressly rejected the distinction between major and minor deficiencies created by Browrtr-Wilbert. See Wesely, 806 N.W.2d at 41-42.6
The effect of today’s application of Brown-Wilbert is that plaintiffs in professional malpractice cases may have refuge in the safe harbor if their affidavits contain only “minor deficiencies,” however defined, while those in medical malpractice cases may have refuge for both major and minor deficiencies. This disparate treatment of similar statutory provisions makes no sense. But I acknowledge that the disparity is required by our existing case law.
When the right case arrives, the obvious solution to this contradiction is to conform Broum-Wilbert to Wesely and thereby return to the plain language of the safe harbor of section 544.42, subdivision 6(c). I acknowledge that, under Brown-Wilbert, baseless claims are dismissed 60 days earlier than they would be if allowed into the safe harbor. But that benefit is far outweighed by two costs: damage to our bedrock principle of statutory interpretation, and the premature death of potentially meritorious claims.
Although we are “extremely reluctant” to overrule our previous cases, “stare deci-sis does not bind us to unsound principles.” Oanes v. Allstate Ins. Co., 617 N.W.2d 401, 406 (Minn.2000). The principle of Brown-Wilbert is fundamentally unsound. The principle of Wesely is sound, and we should follow it in all malpractice cases.
*56Therefore, I respectfully concur in the result.
. Further, as discussed in the amicus brief of Minnesota Defense Lawyers Association, it is not entirely clear whether proximate cause in this case is even a question of fact for the jury, or rather a question of law for the court. Compare Wartnick, 490 N.W.2d at 115 ("The determination of proximate cause is normally a question of fact for the jury.... However, if reasonable minds cannot disagree, proximate cause becomes a question of law.”), and Restatement (Third) of Torts: Liability for Physical and Emotional Harm § 29 cmt. q. (Am. Law Inst.2010) ("Scope of liability is a mixed question of fact and law, much like negligence. As with negligence, the court’s role is to instruct the jury on the standard for scope of liability when reasonable minds can differ as to whether the type of harm suffered by the plaintiff is among the harms whose risks made the defendant’s conduct tortious, and it is the function of the jury to determine whether the harm is within the defendant’s scope of liability.”), with William L. Prosser, The Minnesota Court on Proximate Cause, 21 Minn. L. Rev. 19, 27 (1937) (arguing, regarding unforeseeable consequences and proximate cause, that the "question is not one of causation, for the causal connection is clear and direct, without intervening forces of any kind. It is rather one of policy, as to whether defendant’s responsibility for its admitted fault is to be extended to such results.”).
. The only statutory language cited by Brown-Wilbert to support its holding is the existence of the 180-day requirement. But it does not explain why the 180-day requirement would be so "meaningless,” see Brcwn-Wilbert, 111 N.W.2d at 217-18, without the “meaningful disclosure" standard.. After receiving notice of deficiencies upon a motion to dismiss, a *54plaintiff has only 60 days to cure them; any uncured deficiencies result in mandatory dismissal. And if a plaintiff provides neither an affidavit nor an answer to an interrogatory within the 180-day period, by the plain words of the statute, the safe harbor is not available. See Minn.Stat. § 544.42, subd. 6(c) (stating that the district court must issue “specific findings as to the deficiencies of the affidavit or answers to interrogatories,” implying that such affidavit or answers to interrogatories must exist in the first place).
. The majority states that "[i]n order to give life to the second affidavit requirement, we have read a limitation into the safe-harbor provision of” the statute. Exactly; Brown-Wilbert added to the letter of the law under the pretext of pursuing its purported spirit.
. Such alternatives included the authorization of a deposition of the expert at the plaintiff’s expense or a limitation of the expert’s testimony to those matters adequately disclosed, Sorenson, 457 N.W.2d at 193.
. Justice Paul Anderson, who wrote a strong and prescient dissent in Brown-Wilbert, 732 N.W.2d at 225-31, expressing concern that the "minor deficiencies” standard would work injustices, joined the unanimous court in Wesely. The other Brown-Wilbert dissenter, Justice Alan Page, took no part. Wesely, 806 N.W.2d at 44.
. Wesely justified treating the safe harbors of the two statutes differently because the professional malpractice statute provides that the district court triggers the start of the safe-harbor period by way of giving notice, while the medical malpractice statute's safe harbor is "automatic” and does not require the court to give notice. 806 N.W.2d at 41-42. This is a distinction without a difference, as the professional malpractice statute’s safe-harbor provision is likewise automatic upon a motion to dismiss. Such a motion "shall not be granted unless” the court provides notice of the deficiencies and time to cure them. Minn.Stat. § 544.42, subd. 6(c).