Associate Chief Justice NEHRING, opinion of the Court:
INTRODUCTION
¶ 1 The Federal District Court for the District of Utah has certified the following question to this court:
Does section 78B-3-425 of the Utah Code clarify existing law and therefore retroactively apply to bar negligent credentialing claims that arose prior to its enactment?
Utah Code section 78B-3-425 reads:
Prohibition on cause of action for negligent credentialing. It is the policy of this state that the question of negligent credentialing, as applied to health care providers in malpractice suits, is not recognized as a cause of action.
We hold that Utah Code section 78B-3-425, because it is a substantive amendment and contains no expression of retroactivity, does not apply retroactively (to its effective date), and therefore does not bar Plaintiffs' claim which arose prior to its enactment.
BACKGROUND
¶ 2 On May 24, 2010, Melissa Waddoups underwent several gynecological procedures performed by Dr. Barry Noorda at Logan Regional Hospital, an Intermountain Health Care (IHC) facility. Mr. and Mrs. Waddoups allege Dr. Noorda negligently performed those procedures and they suffered harm as a result. The sole claim relevant to this appeal is the Waddoups' fifth cause of action against IHC alleging negligent credentialing. Mr. and Mrs. Waddoups maintain that IHC failed to exercise reasonable care in granting privileges to Dr. Noorda and failed to properly credential Dr. Noorda, and as a result, he performed surgical procedures on Mrs. Waddoups that he was not qualified to perform. The Waddoups seek the same damages for negligent credentialing as they do for their claims for health care malpractice and negligence.
¶ 3 On May 14, 2010, this court issued its opinion in Archuleta v. St. Mark's Hospital.1 In that case, we were asked to decide whether Utah Code sections 58-13-5(7),2 58-13-4(2),3 and 26-25-14 granted hospitals immunity from negligent credentialing claims. A majority of this court concluded that "the legislature did not intend to immunize negligent credentialing claims brought by patients" in its enactment of any of these three statutes, and "therefore formally recognize[d] negligent credentialing as a valid common-law cause of action."5 We held negligent credentialing to be "simply the application of broad common law principles of negligence," and a "natural extension of torts such as negligent hiring."6
¶ 4 The following year, the Utah Legislature passed Senate Bill 150, subsequently codified on May 10, 2011 as section 78B-3-425, which reads:
Prohibition on cause of action for negligent credentialing. It is the policy of this state that the question of negligent credentialing, as applied to health care providers in malpractice suits, is not recognized as a cause of action.
This case concerns the effect of section 78B-3-425 on the Waddoups' claims, specifically, whether section 78B-3-425 retroactively bars Plaintiffs' negligent credentialing claim which accrued before the enactment of the statute.
STANDARD OF REVIEW
¶ 5 "A certified question from the federal district court does not present us with a decision to affirm or reverse a lower court's decision; as such, traditional standards of review do not apply. On certification, we answer the legal questions presented without resolving the underlying dispute."7
ANALYSIS
¶ 6 It is well established that "[t]he courts of this state operate under a statutory bar against the retroactive application of newly codified laws," and therefore "parties' substantive rights and liabilities are determined by the law in place at the time when a cause of action arises."8 The statute barring retroactive application of new laws contains a single exception, "[a] provision of the Utah Code is not retroactive, unless the provision is expressly declared to be retroactive."9 "Thus, absent clear legislative intent to the contrary, we generally presume that a statute applies only prospectively."10 "The intent to have a statute operate retroactively may be indicated by explicit [statutory] statements" to that effect, "or by clear and unavoidable implication that the statute operates on events already past."11 Like all matters of statutory interpretation, we evaluate retroactivity by first examining the text of the statute, because "[i]t is axiomatic that the best evidence of legislative intent is the plain language of the statute itself."12 "Only when we find ambiguity in the statute's plain language need we seek guidance from the legislative history and relevant policy considerations."13
¶ 7 The statutory language in this case is a single sentence: "It is the policy of this state that the question of negligent credentialing, as applied to health care providers in malpractice suits, is not recognized as a cause of action."14 This phrase contains no words indicative of retroactive application,15 nor does any language appear that evinces a "clear and unavoidable implication that the statute operates on events already past."16 Both of the verbs which appear in the sentence are in present tense: "is" and "is not recognized."17 It simply cannot be said that the use of the present tense communicates a clear and unavoidable implication that the statute operates on events already past. If anything, use of the present tense implies an intent that the statute apply to the present, as of its effective date, and continuing forward. There is nothing ambiguous about the statute that would necessitate further analysis beyond the plain language. However, that does not end our analysis.
¶ 8 In addition to the single statutory exception, we have long recognized a distinction between substantive and procedural laws as it relates to retroactive application of newly enacted statutes.18 Laws that "enlarge, eliminate, or destroy vested or contractual rights" are substantive and are barred from retroactive application absent express legislative intent.19 However, laws which "merely pertain[] to and prescribe[] the practice and procedure or the legal machinery by which the substantive law is determined or made effective" are procedural and "may be given retrospective effect."20 In purporting to eliminate the cause of action of negligent credentialing, section 78B-3-425 cannot be said to be merely procedural, but rather is clearly substantive in nature. IHC concedes this point.
¶ 9 IHC argues that section 78B-3-425 is merely a clarifying amendment and thus subject to the judicially-created exception that "when the purpose of an amendment is to clarify the meaning of an earlier enactment, the amendment may be applied retroactively in pending actions."21 However, since the time oral argument was heard in this case, this court has decided Gressman v. State,22 which repudiated such exception. In Gressman, we noted that although
our case law has occasionally referred to "amendments clarifying statutes" as an "exception" to the retroactivity ban, we have never applied them as such. Instead, our retroactivity case law has invoked this "exception" only in connection with statutory amendments that we have characterized as procedural. And when our cases discuss the "clarifying amendment exception," it is always in tandem with or as a counterpart to our analysis of the above-noted distinction between substance and procedure.... The governing statute ... makes no express room for an exception for clarifying amendments per se. The sole exception spelled out explicitly by statute requires an express provision for retroactivity.23
¶ 10 Having repudiated the sole exception IHC relies on in this case, our work is done. The statute is not retroactive.
¶ 11 We note that our repudiation of the clarifying amendment exception does not deny the legislature the opportunity to clarify statutes and have such clarifications act retroactively. Rather, it requires the legislature to convey such intent expressly in the language of the statute if it desires such effect.
¶ 12 Having found that the statute does not apply retroactively, we need not address any of the constitutional issues raised.
CONCLUSION
¶ 13 In sum, we answer the certified question in the negative; section 78B-3-425 of the Utah Code does not apply retroactively to bar negligent credentialing claims that arose prior to its enactment.
Chief Justice DURRANT, Justice PARRISH, Justice LEE, and Judge CHRISTIANSEN joined. Having recused herself, Justice DURHAM does not participate herein; Court of Appeals Judge MICHELE M. CHRISTIANSEN sat.
