A federal grand jury indicted Steven DeLia on one count of healthcare fraud . See 18 U.S.C. § 1347 . But the government filed the indictment outside the ordinarily applicable statute of limitations-that is, more than five years after DeLia's charged conduct occurred. See 18 U.S.C. § 3282 (a). Even so, for two independent reasons, the government argues that the indictment was timely: (1) that the Wartime Suspension of Limitations Act suspended the limitations period from running in this case , see 18 U.S.C. § 3287 ; and (2) that DeLia waived his asserted statute-of-limitations defense. We reject both reasons and conclude that the prosecution is time-barred. Exercising jurisdiction under 28 U.S.C. § 1291 , we reverse and remand with instructions to vacate DeLia's conviction and dismiss the indictment.

BACKGROUND

In 2009, DeLia, then a licensed physician, opened a medical clinic in Sallisaw, Oklahoma, practicing family medicine and psychiatry. He also served as a member of the United States Army Reserve. In mid-2010, DeLia learned that the Army would deploy him to Afghanistan, so he began preparing the clinic for his absence.

At that time, DeLia's staff included two licensed practical nurses, LeeAnn Dewberry and Jennifer Campney, and one physician's assistant, Susan Davis (PA Davis). Under Oklahoma law, licensed practical nurses cannot prescribe Schedule II controlled substances. See Okla. Stat. tit. 59 § 567.4a ; Okla. Stat. tit. 63 § 2-312(C). But Oklahoma law permits physician's assistants to prescribe Schedule II controlled substances 1 if acting under a physician's *1215 supervision and if the controlled substance is administered onsite. Okla. Stat. tit. 59 § 519.6(D).

To keep his clinic open while he was deployed, DeLia signed pads of blank prescription forms for the clinic staff's use. This enabled the clinic staff to write prescriptions by simply completing the prescription forms with the patient's name, the drug, and the dosage. In total, DeLia signed about 5,000 blank prescriptions to prepare the clinic for his four-month deployment. PA Davis used the signed prescription forms to write prescriptions for Schedule II controlled substances. Among those receiving her prescriptions for Schedule II controlled substances were DeLia's pain-management patients, a group making up a significant portion of DeLia's practice. Though DeLia looked for a physician to supervise PA Davis during his deployment, he failed to obtain one.

In mid-October 2010, DeLia left Sallisaw to visit family before reporting to Fort Benning at month's end. Appellant's App. vol. 3 at 632:5-9. In early November, the Army sent DeLia from Fort Benning to Kuwait and then to Afghanistan.

About two weeks after Delia left Sallisaw, the Oklahoma Board of Medical Licensure (the Board) learned from an anonymous caller that DeLia was out of state and that his office staff was prescribing controlled substances with DeLia's pre-signed, blank prescription forms. In addition, the Oklahoma State Pharmacy Board received calls from pharmacists reporting that they had received new prescriptions for Schedule II controlled substances from DeLia, who they believed was not in Oklahoma.

Two Board investigators traveled to DeLia's clinic where they questioned the clinic staff. According to the Board's records, DeLia was PA Davis's sole supervising physician. PA Davis confirmed this to investigators. While at the clinic, investigators confiscated 5,625 blank pre-signed prescriptions and a sign-out log showing that the clinic's staff had already used 4,330 pre-signed prescriptions between March 1, 2010 and November 3, 2010. Even before the Army told DeLia that it would deploy him in October, DeLia had pre-signed blank prescriptions for use when he was out of the clinic, including while he was vacationing. DeLia had also previously allowed clinic staff to use pre-signed, blank prescription forms to prescribe controlled substances even when he was working in the clinic-to increase office efficiency.

In February 2011, DeLia returned to Sallisaw. In December 2011, the Board filed a disciplinary action against DeLia, alleging that he had engaged in unprofessional conduct by pre-signing prescription forms for his staff to use while he was gone and by directing PA Davis to provide healthcare services despite his failure to secure for her a supervising physician. Okla. Stat. tit. 59 § 519.6(A). In March 2012, DeLia surrendered his medical license in lieu of prosecution by the Board.

In January 2016, DeLia met with federal prosecutors and signed a waiver of the applicable statute of limitations for "offenses, including but not limited to, conspiracy to commit health care fraud, health care fraud and money laundering." Appellant's App. vol. 1 at 34-36. In the waiver, DeLia acknowledged knowing that he was a target of a federal grand-jury investigation related to "his conduct causing false claims to be filed and for receiving health care payments from Medicare, Medicaid, and Tricare for services not provided from 2010 through 2011." Appellant's App. vol. 1 at 34 ¶ 1. The waiver further stated that DeLia desired to "extend" the applicable statute of limitations. Id. at 34 ¶ 2. Specifically, the waiver stated that DeLia had been "advised that if, in fact, the statute of *1216 limitations as to any of the specified offenses were to expire during the period agreed upon," the waiver "would extend the period during which he could be prosecuted for such criminal violations." Id. at 35 ¶ 3. DeLia agreed to waive the statute of limitations "for the period from the date of his execution of this Waiver [January 5, 2016] through and including July 31, 2016." Id. at 36 ¶ 8.

On June 15, 2016, a federal grand jury indicted DeLia on one count of healthcare fraud, see 18 U.S.C. § 1347 . 2 The indictment alleged that "[b]eginning February 1, 2010, and continuing through November 9, 2010" DeLia had "devised and executed a scheme to defraud the Oklahoma Medicaid program by causing the filing of false claims and receiving Medicaid payments for medical services not rendered by a qualified medical professional." Id. at 15-16 . Three months before trial, DeLia moved to dismiss the indictment, arguing that the statute of limitations had expired. The district court denied DeLia's motion, concluding that the indictment was timely because the Suspension Act had tolled the statute of limitations. The case proceeded to trial.

After the government presented its case, DeLia moved for the district court to reconsider his motion to dismiss based on the statute of limitations. The district court denied DeLia's motion. The jury convicted DeLia of healthcare fraud. DeLia appealed the district court's denial of his motion to dismiss and his conviction. 3

DISCUSSION

On appeal, DeLia argues that the district court erred in ruling that the statute of limitations hadn't expired. First, DeLia argues that the Suspension Act applies to war-related frauds against the federal government, not to healthcare fraud against a state agency. Second, he argues that the government cannot use a waiver to revive an already-expired limitations period. Third, DeLia argues that even if a waiver could revive an already-expired limitations period, the waiver would be unenforceable because he didn't knowingly execute it, meaning he didn't know when he signed the waiver that the statute of limitations had already expired for what would ultimately be the charged conduct. 4 We address each of these arguments after identifying our standard of review and discussing the applicable criminal statute of limitations.

I. Standard of Review

We review de novo a district court's interpretation and application of a statute of limitations. Barnes v. United States , 776 F.3d 1134 , 1139 (10th Cir. 2015). And we review de novo the question of whether a defendant's express waiver of the statute of limitations is enforceable.

*1217 United States v. Flood , 635 F.3d 1255 , 1258 (10th Cir. 2011).

II. The Statute of Limitations

The government had five years from DeLia's alleged criminal conduct to indict him. See 18 U.S.C. § 3282 (a). 5 A "statute of limitations reflects a legislative judgment that, after a certain time, no quantum of evidence is sufficient to convict." Stogner v. California , 539 U.S. 607 , 615, 123 S.Ct. 2446 , 156 L.Ed.2d 544 (2003). This time limit "is designed to protect individuals from having to defend themselves against charges when the basic facts may have become obscured by the passage of time and to minimize the danger of official punishment because of acts in the far-distant past." Toussie v. United States , 397 U.S. 112 , 114-15, 90 S.Ct. 858 , 25 L.Ed.2d 156 (1970). Statutes of limitations also encourage law enforcement to promptly investigate suspected criminal activity. Id. at 115 , 90 S.Ct. 858 .

A statute of limitations "provides a nonjurisdictional defense, not a jurisdictional limit." Musacchio v. United States , --- U.S. ----, 136 S.Ct. 709 , 718, 193 L.Ed.2d 639 (2016). So a defendant must affirmatively and timely raise a statute-of-limitations defense. Id. at 717-18 . When a defendant does so, "the Government then bears the burden of establishing compliance with the statute of limitations by presenting evidence that the crime was committed within the limitations period or by establishing an exception to the limitations period." Id. at 718 .

Here, the indictment charged DeLia with criminal conduct occurring between February 1, 2010 through November 9, 2010. So absent an exception, the statute of limitations would have expired on November 9, 2015. But the government didn't file the indictment until June 15, 2016. To excuse its delay, the government argues two independent positions: (1) that the Suspension Act tolled the statute of limitations, and (2) that, even if the statute of limitations did expire, DeLia waived his statute-of-limitations defense. 6

A. Wartime Suspension of Limitations Act

"When the United States is at war or Congress has enacted a specific authorization for the use of the Armed Forces," the Suspension Act suspends the statute of limitations for certain offenses "until 5 years after the termination of hostilities." 18 U.S.C. § 3287 . Congress enacted the Suspension Act to guard against the increased potential of fraud against the federal government during wartime by giving the government more time to discover and prosecute such offenses. See Kellogg Brown & Root Servs., Inc. v. United States, ex rel. Carter , --- U.S. ----, 135 S.Ct. 1970 , 1973, 1975, 191 L.Ed.2d 899 (2015) ; Bridges v. United States , 346 U.S. 209 , 218, 73 S.Ct. 1055 , 97 L.Ed. 1557 (1953). The Suspension Act "creates an exception to a longstanding congressional 'policy of repose' that is fundamental to our society and our criminal law." Bridges , 346 U.S. at 215-16 , 73 S.Ct. 1055 . So the statute "should be 'narrowly construed,' " and any ambiguity should be " 'interpreted in favor of repose.' " Kellogg , 135 S.Ct. at 1978 (quoting Bridges , 346 U.S. at 216 , 73 S.Ct. 1055 ).

*1218 In September 2001, Congress specifically authorized the use of military force "against those responsible for the [September 11, 2001] attacks launched against the United States." Authorization for the Use of Military Force, Pub. L. No. 107-40, 115 Stat. 224 (2001). And in October 2002, Congress specifically authorized the use of military force in Iraq. Authorization for Use of Military Force Against Iraq Resolution of 2002, Pub. L. No. 107-243, 116 Stat. 1498 . Hostilities end within the meaning of the Suspension Act only when "proclaimed by a Presidential proclamation, with notice to Congress, or by a concurrent resolution of Congress." 18 U.S.C. § 3287 .

DeLia acknowledges that the Suspension Act tolls the statute of limitations for some criminal offenses and that, for those offenses, the tolling continues until the President or Congress proclaims the termination of hostilities. But DeLia disputes that the Suspension Act applies to his charged offense-defrauding a state healthcare benefit program. The Suspension Act applies to any offense:

(1) involving fraud or attempted fraud against the United States or any agency thereof in any manner, whether by conspiracy or not, or (2) committed in connection with the acquisition, care, handling, custody, control or disposition of any real or personal property of the United States, or (3) committed in connection with the negotiation, procurement, award, performance, payment for, interim financing, cancelation, or other termination or settlement, of any contract, subcontract, or purchase order which is connected with or related to the prosecution of the war or directly connected with or related to the authorized use of the Armed Forces, or with any disposition of termination inventory by any war contractor or Government agency.

18 U.S.C. § 3287 .

Offenses involving fraud covered by the Suspension Act are "limited strictly to offenses in which defrauding or attempting to defraud the United States is an essential ingredient of the offense charged." Bridges , 346 U.S. at 221 , 73 S.Ct. 1055 . 7 In Bridges , the Court held that the Suspension Act didn't apply to offenses charging knowingly making a false statement under oath in naturalization proceedings, because the offenses didn't "involve the defrauding of the United States in any pecuniary manner or in a manner concerning property." Id.

*1219 By contrast, in United States v. Grainger , 346 U.S. 235 , 237, 241-45, 73 S.Ct. 1069 , 97 L.Ed. 1575 (1953), the Court held that the Suspension Act did apply to false claims for wool purchases from a federal agency (the Commodity Credit Corporation), because defrauding the federal government was "an essential ingredient of the offenses charged."

To determine whether the Suspension Act applies, we must evaluate the elements of the charged offense. Bridges , 346 U.S. at 222-23, 73 S.Ct. 1055 . Here, DeLia was charged with healthcare fraud under 18 U.S.C. § 1347 , which makes it unlawful to "defraud any health care benefit program ... in connection with the delivery of or payment for health care benefits, items, or services." A "health care benefit program" is "any public or private plan or contract ... under which any medical benefit, item, or service is provided to any individual." 18 U.S.C. § 24 (b).

DeLia argues that the Suspension Act doesn't apply to § 1347, because Congress enacted the Suspension Act to combat war-related fraud. And, he says, the charged offense involves not war-related fraud against the federal government, but healthcare fraud against a state agency.

The government responds that the Suspension Act applies because Medicaid is a federal-state partnership that involves a substantial expenditure of federal funds. 8 From there, the government argues that the charged offense fits into two of the three offense categories covered by the Suspension Act-first, offenses involving fraud against the federal government; and second, offenses committed in connection with the federal government's property (here, federal funds). We conclude that the government has failed to establish that the Suspension Act applies to the charged offense.

Though the government argues that Medicaid fraud 9 constitutes fraud against the United States or a federal agency, the charged offense-healthcare fraud-contains no element requiring proof that DeLia defrauded the federal government. Instead, *1220 § 1347 requires proof that DeLia defrauded a "health care benefit program." The district court instructed the jury that the government had to prove four elements beyond a reasonable doubt:

First : the defendant devised a scheme or artifice to defraud a health care benefit program in connection with the delivery of or payment for health care benefits, items or services;

Second : the defendant executed or attempted to execute this scheme or artifice to defraud;

Third : the defendant acted knowingly and willfully with the intent to defraud; and

Fourth : the scheme to defraud employed false or fraudulent pretenses, representations, or promises.

Appellant's App. vol. 1 at 135. Nothing required the jury to find that DeLia had defrauded the federal government or a federal agency. In fact, the indictment alleged that DeLia had executed a scheme "to defraud money and property owned by and under the custody and control of the Oklahoma Health Care Authority, a health benefit program." Appellant's App. vol. 1 at 16.

At trial, the government presented evidence that the healthcare benefit program DeLia defrauded was the Oklahoma Health Care Authority ("the Authority"). This evidence included testimony from the Authority's employees and DeLia's former office staff. One Authority employee, Amy Bradt, testified about the provider agreement that DeLia and the Authority had signed, which required DeLia to provide medical services in accordance with his license and to comply with the rules and regulations of the Authority. Another Authority employee, Jean Krieske, testified about the supervision requirements for physician's assistants and their prescriptive authority, particularly the limited circumstances in which they can prescribe Schedule II controlled substances.

PA Davis, who had served as DeLia's physician's assistant during the time period alleged in the indictment, testified about using the pre-signed prescription forms to prescribe Schedule II controlled substances that she knew she couldn't lawfully prescribe. PA Davis also testified that she had no supervising physician while DeLia was deployed. Finally, Justin Etchieson, a data analyst at the Oklahoma Attorney General's Office Medicaid Fraud Control Unit, testified about the claims that the Authority had paid for services provided at DeLia's clinic and for Schedule II prescriptions.

The government also presented evidence that the Authority is a state agency. Bradt testified that the Authority is "the state Medicaid agency," meaning it is the "one state agency that processes and pays Medicaid claims[.]" Appellant's App. vol. 1 at 204:17-22. And Etchieson testified that the Authority is "the state agency that administers the Medicaid program." Appellant's App. vol. 2 at 548:12-15. So the charged offense involved fraud against a state agency, not the federal government or a federal agency. 10

*1221 Faced with this fact, the government argues that the Suspension Act applies because the federal government partly funds Oklahoma's Medicaid program. We have already concluded that the charged offense doesn't have as an element fraud against the federal government, so we next analyze the government's argument in the context of the second category of offenses, those committed in connection with the federal government's property. See 18 U.S.C. § 3287 .

At trial, Bradt testified that the Authority uses federal and state funds to satisfy claims. But the government wasn't required to prove that the funds the federal government distributes to the Authority continue to belong to the federal government. Instead, the indictment alleged that the offense involved money and property owned by the Authority. At trial, the government presented evidence that the offense involved claims submitted to and paid by the Authority.

Though the Authority receives federal funds, that fact alone is insufficient to bring the charged offense within the scope of the Suspension Act. The charged offense must be committed in connection with the federal government's property, see 18 U.S.C. § 3287 , a fact that the government wasn't required to prove for the jury to find DeLia guilty of the charged offense. And the government cites no authority for the proposition that defrauding a program partially funded by federal money qualifies as an offense committed in connection with the federal government's property. Accepting the government's argument would require us to expand the scope of the Suspension Act beyond any court's previous constructions of the statute. 11

We conclude that the Suspension Act does not apply to the charged offense. Interpreting the Suspension Act to extend beyond offenses against the federal government and its agencies would be inconsistent with the narrow construction we must give the statute and wouldn't serve the statute's purpose-providing the federal government with additional time to discover and prosecute offenses against it during wartime.

B. Waiver

We have previously held "that defendants can expressly waive the bar to *1222 prosecution established by the statute of limitations." United States v. Flood , 635 F.3d 1255 , 1258 (10th Cir. 2011). For a waiver to be enforceable, the defendant must knowingly and voluntarily execute the waiver. See id. at 1259 . DeLia argues that his waiver of the statute of limitations is unenforceable because he didn't know that the statute of limitations governing the charged conduct had already expired before he signed the waiver.

After examining the waiver's language, we conclude that DeLia didn't waive his right to enforce the expired portion of the statute of limitations applying to his charges. So we agree with DeLia that he did not knowingly waive his right to assert the statute of limitations, but we do so for a reason one step back in the analysis-we hold that by the waiver's own terms DeLia did not waive, knowingly or unknowingly, the statute of limitations for the charges the government elected to pursue.

When determining the scope of a waiver, we "must strictly construe any ambiguities in the agreement against the government (the drafter) and in favor of the defendant." United States v. Gordon , 480 F.3d 1205 , 1207 (10th Cir. 2007). "This means waivers should be narrowly construed." Id. Narrow construction of a waiver of the statute-of-limitations defense is also appropriate because criminal statutes of limitations are "to be liberally interpreted in favor of repose." United States v. Reitmeyer , 356 F.3d 1313 , 1317 (10th Cir. 2004) (quoting United States v. Marion , 404 U.S. 307 , 322 n.14, 92 S.Ct. 455 , 30 L.Ed.2d 468 (1971) ).

Here, the waiver purports to extend the limitations period, not to revive an already expired limitations period. The waiver states that DeLia "understands that absent such a waiver the United States would be prohibited from prosecuting him for violations of certain criminal offenses ... after a period of five years has elapsed from the last date of the violations." Appellant's App. vol. 1 at 35 ¶ 3. The waiver next states that DeLia had been "advised that if, in fact, the statute of limitations as to any of the specified offenses were to expire during the period agreed upon in this document, this Waiver would extend the period during which he could be prosecuted." Id. (emphasis added). The language "after a period of five years has elapsed" and "were to expire" indicates that the statute of limitations had not yet expired. Likewise, DeLia agreed to waive the statute of limitations for a specified period-"from the date of his execution of this Waiver [January 5, 2016] through and including July 31, 2016." Id. at 36 ¶ 8. Along the same line, the waiver speaks of DeLia's tolling "the applicable statute of limitations effective as of the date of his execution of this waiver [January 5, 2016], through and including July 31, 2016." Id. at 35 ¶ 3. This time period further suggests that the waiver excludes any statute of limitations that had already expired when DeLia executed the waiver. Especially when we narrowly construe the waiver against the government, we conclude that this language defeats any government argument that this waiver in fact revived an already-expired limitations period.

For the charged crime, the statute of limitations expired before DeLia signed the waiver. Accordingly, the time period charged in the indictment did not fall within the scope of the agreed extension-January 5, 2011 until July 31, 2011. So the statute of limitations expired on November 9, 2015. That being so, we hold that DeLia has a right to assert his winning statute-of-limitations defense.

CONCLUSION

For the foregoing reasons, we reverse the district court's denial of DeLia's motion *1223 to dismiss and remand with instructions to vacate DeLia's conviction and dismiss the indictment.