FOR PUBLICATION



### UNITED STATES COURT OF APPEALS FOR THE NINTH CIRCUIT

BOGDAN RADU,

Petitioner

- Appellee

,

v.

PERSEPHONE JOHNSON SHON,

Respondent

- Appellant

. No. 22

- 16316

D.C. No. 4:20

- cv

- 00246

- RM

OPINION

Appeal from the United States District Court for the District of Arizona Rosemary Márquez, District Judge, Presiding

Argued and Submitted November 21, 2022 San Francisco, California

Filed March 13, 2023

Before: Mary H. Murguia, Chief Judge, and Ryan D. Nelson and Danielle J. Forrest, Circuit Judges.

Opinion by Judge R. Nelson ; Concurrence by Chief Judge Murguia2 R ADU V

. S HON

SUMMARY *

Hague Convention

The panel affirmed the district court’s order granting, on a second remand, Bogdan Radu’s petition against Persephone Johnson Shon for the return, pursuant to the Hague Convention, of the parties’ two children to Germany. The district court held an evidentiary hearing and granted Radu’s petition. The district court found a grave risk of psychological harm if the children were returned to Germany in the custody of Radu, but it determined that those risks would be mitigated if the children returned in Shon’s temporary custody. The district court ordered Shon to return with the children and retain full custody until the German courts resolved the merits of the parties’ custody dispute. On appeal, in Radu I , the panel vacated and remanded for the district court to determine whether the sole-custody measu re would be enforceable in Germany. On remand, the district court held a second hearing. In a second return order, the district court concluded that the enforceability of the sole

- custody remedy was uncertain but was no longer necessary. Based on new evidence that a German court would take months to resolve custody, the district court held that ordering Shon to return with the children to Germany, where the default rule was joint custody, sufficiently ameliorated the risk of psychological harm. Shon ag ain appealed. The panel remanded for

* This summary constitutes no part of the opinion of the court. It has been prepared by court staff for the convenience of the reader.R ADU V

. S HON 3

reconsideration in light of Golan v. Saada , 142 S. Ct. 1880 (2022), which clarified that, where there is a grave risk that a child’s return would expose the child to physical or psychological harm, consideration of ame liorative measures is discretionary rather than mandatory.
On remand, the district court ordered return based on the existing record. Following Golan , the district court exercised discretion to consider ameliorative measures. The district court again s tated that ordering Shon to return to Germany with the children would ameliorate the risk of psychological harm. Shon filed the current appeal. On a limited remand, the district court issued a clarifying order. Agreeing with other circuits, the panel hel d that, in cases governed by the Hague Convention, the district court has discretion as to whether to conduct an evidentiary hearing following remand and must exercise that discretion consistent with the Convention. The panel held that, on the second rema nd, the district court did not abuse its discretion in declining to hold a third evidentiary hearing when the factual record was fully developed. The panel held that, in making determinations about German procedural issues, the district court neither abuse d its discretion nor violated Shon’s due process rights by communicating with the State Department and, through it, the German Central Authority. The panel further held that the Federal Rules of Evidence and its hearsay rules do not apply to foreign law m aterials. Finally, the panel held that the record provided adequate support for the district court’s fact findings underlying its clarified return order, and the law

- of

- the

- case doctrine did not prevent the district court from revisiting its prior ruling

o n grave risk. The panel therefore affirmed the district4 R ADU V

. S HON

court’s grant of the petition for the children’s return with the ameliorative measures ordered by the district court. Concurring, Chief Judge Murguia wrote that she concurred fully in the principal o pinion. She wrote separately to express her view that, in Radu I , the panel should not have declined to allocate a burden of proof on the reasonableness of an ameliorative measure. Chief Judge Murguia wrote that a future panel should follow other circuit s and hold that, when a petitioner proffers a measure to ameliorate the grave risk of harm, it is the petitioner’s burden to establish that the measure is reasonably appropriate and effective.

COUNSEL

Kelly A. Powers (argued) and Stephen J. Cullen, Miles & Stockbridge PC, Washington, D.C.; Shaun P. Kenney, The Kenney Law Firm PC, Tucson, Arizona; for Respondent

Appellant. Michelle E. Irwin (argued), Fenwick & West LLP, Seattle, Washington; Rina Plotkin and Todd R. Gregorian, Fenwick & West LL P, San Francisco, California; for Petitioner

Appellee.R ADU V

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OPINION

R. NELSON
, Circuit Judge :
This is the third appeal in a n international child custody dispute between Persephone Johnson Shon and Bogdan Radu over their minor children. While the family was residing in Germany, Shon took the children to the United States and has refused to return them

. T he Hague Convention generally require s children to be returned to the state of habitual residenc e so that country’s courts may adjudicate the merits of any custody disputes

. We
pre viously vacated and remanded the district court’s first order to return the children to Germany. See Radu v. Shon

, 11 F.4th 1080 (9th Cir. 2021) [ Radu I ]
, vacated

, 142 S. Ct. 2861 (2022)

, in light of Golan v. Saada , 142 S. Ct. 1880 (2022). Because the Supreme Court issued its decision in Golan while we were considering Shon’s appeal of the second return order, we also remanded that order for the district court’s reconsiderati on. The district court then granted the petition a third time. We now affirm.

I

A

The Hague Convention on the Civil Aspects of International Child Abduction (Convention), Oct

. 25, 1980, T.I.A.S. No. 11670, “address[e s ] ‘the problem of international child abductions during domestic disputes.’” Lozano v. Montoya Alvarez , 572 U.S. 1, 4 (2014) (quoting Abbott v. Abbott , 560 U.S. 1, 8 (20 1 0) ). It aims “to secure the prompt return of children wrongfully removed” and “ensure that rights of custody and of access” are respected

across Contracting States

. Convention Art. 1. A ll6 R ADU V

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signatories must “use the most expeditious procedures available” to implement t hese goals. Convention Art. 2. Contracting States must also create Central Authorit ies to facilitate cooperatio n. Convention Art. 6 & 7. Domestically, the International Child Abduction Remedies Act ( ICARA ) implements the Convention’s rule s , creates the United States Central Authorit y , and gives our courts jurisdiction to adjudicate disputes under the Convention . 22 U.S.C. § 9001 et seq. “The Convention’s central operating feature is the return remedy.” Abbott , 560 U.S. at 9. Th is remedy is “provisional” because it merely “fixes the forum for custody proceedings” and leaves the merits to the country of habitual residence. Monasky v. Tag lieri , 140 S. Ct. 719, 72 3 (2020) (internal quotation marks and citation omitted). Under the Convention, court s “shall order the return” of “a child [who] has been wrongfully removed or retained.” Convention Art. 12. Article 13 provides exceptions. Rel evant here, the court “is not bound to order the return” of a child if the party opposing return establishes that “there is a grave risk that [the child’s] return would expose the child to physical or psychological harm

. ” Convention Art. 13(b). Under Article 13(b), courts have “the discretion to grant or deny return .” Golan v. Saada , 142 S. Ct. 1 880, 1892 (2022)

. That discretion allows for the considerat ion of measures that would ameliorate the grave risk

. S ee id. at 18 93

. B

Radu and Shon married in 2011 in the United States. Their older child, O.S.R.
, was born in the United States in 2013, and their younger child, M.S.R.
, was born in Germany in 2016. Both children are citizens of the United States but not German y . From 2016 to 2019, Radu, Shon, and theirR ADU V

. S HON 7

children lived in Germany. Shon took O.S.R. and M.S.R. from Germany to the United States in June 2019

. Shon and the children have since lived with Shon’s parents in Arizona

, despite Radu’s wishes for the children to be brought back to Germany

. 1 Radu petitioned for the children to be returned to Germany in federal district court in Arizona in June 2020

. The district court held an evidentiary hearing and granted Radu’s petition

. The court found a grave risk of psychological harm if the children were returned to Germany in the custody of Radu

. T he court determined , however, that thos e risks would be mitigated if the children returned to Germany in Shon’s temporary custody

. S o the court order ed Shon to return with the children and retain full custody until the German courts resolved the merits of the custody dispute

. At that time, Gau din v. Remis made the consideration of ameliorative measures mandatory. See 415 F.3d 1028, 1035 (9th Cir. 2005) ( “Courts applying ICARA have consistently held that, before denying the return of a child because of a grave risk of harm, a court must conside r alternative remedies that would allow both the return of the children to their home country and their protection from harm.” ( internal quotation marks and citation omitted) ). Shon appealed . W e vacated and remanded for the district court to determine whether the sole

- custody measure would be enforceable in Germany. See Radu I , 11 F.4th at 1089

– 90.

2 On remand, the district court held a second hearing at which Shon presented expert testimony and the parties8 R ADU V

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testified

. Shon’s expert , a Germany

- licensed attorney, stated that the temporary sole

- custody order would not be enforceable because Germany does not recognize ameliorative measures. He also testified that a German court may take up to six months to decide custody because the children would not be considered habitually resident in Germany until then. Furthermore, because the children are not German citizens, he testified that neither Shon nor Radu could initiate German custody proceedings or obtain protective measures from abroad.

Shon testified that her savings would not cover travel or living expenses in Germany but conceded that her parents, who had assisted her financially during this case, had paid for her plane tickets for her previous return from Germany

. She was also afraid of being arrested upon returning to Germany but did not know of any pending legal matters at that time . Radu testified that he would pay for airfare and housing for Shon and their children pending the custody determination. He promised to maintain a separate household and to cooperate with Shon. He also testified that Germany has a child

- protection agency that could ensure the children’s safety if Shon became unavailable.

The district court then contacted the State Department
, Office of Children’s Issues’ country officer for Germany, who contacted the German Central Authority for the court. The court did not receive a binding statement on the time needed for a German court to determine custody

. B ut the German Central Authority cited Section 155 of the Act on Proceedings in Family Matters and Matters of Non

Contentious Jurisdiction, which provides for handling of custody issues “in an expedited manner.” T he German Central Authorit y also confirmed that Germany has youthR ADU V

. S HON 9

welfare office s that may conduct home visits o r take custody of children if necessary

. In a second return order, t he district court concluded that the enforceability of the sole

- custody remedy was uncertain. But that wa s no longer necessary because the district court had considered the risk of psychological harm over too long of a time period

. Based on the new evidence that a German court would take months to resolve custody

, the court held that ordering Shon to return with the children to Germany

— where the default rule was joint custody

— sufficiently ameliorated the risk of psychological harm. Shon again appealed. We stayed the appeal pending the Supreme Court’s resolution of Golan and eventually remanded for reconside ration in light of Golan ’s clarif ication that consideration of ameliorative measures is discretionary rather than mandatory. See 142 S. Ct. at 189 2

– 9 3.

3 The district court did not hold another hearing on the second remand but ordered return based on the existing record. Following Gola n , the district court exercised discretion to consider ameliorative measures. Relying on the second return order ’s analysis , the district court again stated that ordering Shon to return to Germany with the children would ameliorate the risk of psychological harm. It denied Shon’s request for a new evidentiary hearin g, partially because there was no new evidence about Radu’s interactions with the children and partially because a hearing would contra vene the Convention’s directive for expeditious resolution

.10 R ADU V

. S HON

Th e present appeal arises from th e third return order

. Given the parties’ uncertainty about aspects of the ordered remedy , and unresolved logistical issues, we ordered a limited remand while retaining jurisdiction to avoid further delay

. See Friery v. L.A. Unified Sch. Dist. , 448 F.3d 1146, 1150 (9th Cir. 2006) (ordering “a limited remand to the district court”).

We directed the district court to clarify ( 1 ) its current Article 13(b) grave

- risk finding and ameliorative measure(s) ordered , ( 2 ) whether Radu must pay for airfare , ( 3 ) whether Radu must pay for separate living arrangements, ( 4 ) the custody arrangement s (sole or joint) while Shon was temporarily residing in Germany, ( 5 ) the custody arrangements if Shon is no longer able to legally reside in Germany before a German court decides custody, ( 6 ) the need to notify German child protective services upon the children’s arrival, and ( 7 ) whether, if necessary, German child protective s ervices ha ve jurisdiction t o oversee the children’s wellbeing.

The district court answered those questions. First, it explained that the grave risk of psychological harm arose only if the children remained in Radu’s sole custody for a longer time, and that no harm would arise if Shon and Radu had joint custody or if Radu had sole custody for a limited duration. Radu v. Shon , No. CV

- 20

- 00246

- TUC

- RM, 2023 WL 142908, at *2 (D. Ar i z. Jan. 10, 2023). Second, Shon must pay for her and the children’s airfare back to Germany. Id. at *3. Third, Radu must pay for separate living arrangements because Shon would take unpaid leave and could not work in Germany. Id. Fourth, the parties would have joint custody, as German law provides, pending a final custody determination

. Id. Fifth, in the event Shon c ould not remain until the merits decision

, the children would enterR ADU V

. S HON 11

Radu’s physical custody. Id. Sixth, the court determined that notifying German child protective services was unnecessary

. Id. Seventh, the court judicially noticed the existence of jugendamt , the German child protective services agency, and explained that the record suggests that the agency would ha ve authority over the children once they arrive in Germany. Id.

We asked for supplemental briefs about the clarification order ’s effect

. T he issues currently before us are whether the district court should have conducted an evidentiary hearing during the second remand or the limited remand

, refrained from contacting the State Department

, or ultimately determined that the record supported its ameliorative

measure

. II

The Conventio n is in force between the United States and Germany. See Holder v. Holder , 305 F.3d 854 , 859 (9th Cir. 2002) . We have jurisdiction under 28 U.S.C. § 1291 and “review the district court’s factual determinations for clear error, and the district court’s application of the Convention to those facts de novo .” Flores Castro v. Hernandez Renteria , 971 F.3d 882, 886 (9th Cir. 2020).

III

A

Shon contends that the district court should have held a

new evidentiary hearing during the second remand or the l imited remand. She relies on Gaudin ’s inst ruction that

“ [t] he questions before the district court on remand will be whether a grave risk of harm now exists, and if so, whether that risk can be minimized through an alternative remedy

, ”12 R ADU V

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415 F.3d at 1036 , for her position that a new hearing is necessary to determine the current conditions. Neither ICARA nor the Convention specify when a court must hold an evidentiary hearing. ICARA instructs courts to “decide the case in accordance with the Convention.” 22 U.S.C. § 9003(d). And t he Convention directs court s to “a ct expeditiously in proceedings for the return of children.” Convention Art. 11. It also permits a court to “order the return of the child at any time ” notwithstanding the other provisions. Convention Art. 18 (emphasis added). We accordingly review the district court’s decision not to hold a new evidentiary hearing for abuse of discretion

. Under that standard, we affirm the district court unless it c ommits a legal error in interpreting the Convention

, or clearly errs in determining the facts from the record

. See United States v. Hinkson

, 585 F.3d 1247, 1259 (9th Cir. 2009) (en banc). Any categorical rule requiring new hearings would contravene the C onvention’s directive for expeditious resolution. The district court is far better situated to determine the exact procedures necessary

— whether a hearing or supplemental briefing

, for example

— to aid its resolution of the case. A per se rule would impede t hat flexibility with minimal upside

. Under some circumstances, a refusal to hold a new hearing c ould constitute an abuse of discretion

. But t he district court here declined a third evidentiary hearing because the evidence of Radu’s treatment of the children

— on which the court based its ameliorative measure and grave

- risk finding

— had not changed ; Radu had not had contact with the children since the earlier hearings

. Under these circumstances, anotherR ADU V

. S HON 13

hearing would add little to a well

- developed record and needlessly delay proceedings. 1

Our sister circuits agree

. In March v. Levine

, the question presented was whether the district court improperly granted summary judgment to a f ather petitioning for his children’s return without allowing discovery or a hearing on the merits. See 249 F.3d 462, 468 (6th Cir. 2001) . T he Sixth Circuit affirmed. Recognizing that Convention cases are unique, the court explained that “neither [the Convention nor ICARA] expressly requires a hearing or discovery” ; instead they require “expeditious action.” Id. at 474. The court also found persuasive that “courts in other Contracting States to the treaty have also upheld summary procee dings on review.” Id. at 475 (discussing Australian court proceedings).

The Tenth Circuit reached the same conclusion in West v. Dobrev , reasoning that Article 18’s permission to order return at any time provides trial courts “a substantial degree of di scretion in determining the procedures necessary to resolve a petition filed pursuant to the Convention and ICARA.” 735 F.3d 921, 929 (10th Cir. 2013)

. We find these decisions persuasive and conclude that Gaudin does not require otherwise. There, we sa id that the lapse of time made it “unnecessary for us to evaluate the merits of the district court’s finding that a grave risk of psychological harm” existed five years ago. Gaudin , 415 F.3d at 1036. This was because the court should “consider

1 Shon asserts that she would have presented a child psychology expert
at the new hearing

. When Shon previously tried to introduce that expert
at the second hearing , she did not object to the district court’s exclusion of the expert

.14 R ADU V

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the effect of any possible remedies in ligh t of circumstances as they exist in the present.” Id. We did not, however, specify the way the district court should consider present circumstances or mandate a new evidentiary hearing upon

e very remand.

We now hold that , in cases governed by the Conve ntion, the district court has discretion as to whether to conduct an evidentiary hearing following remand and must exercise that discretion consistent with the Convention

. 2 The district court did not abuse its discretion in declining to hold a third evidentiary hearing when the factual record was fully developed.

B

Shon next asserts that the district court’s

co mmunications with the State Department and the German Central Auth orit y were ex parte , resulted in hearsay evidence , and violated Shon’s due process rights

. We once “treat[ed] questions of foreign law as questions of fact to be pleaded and proved.” de Fontbrune v. Wofsy

, 838 F.3d 992, 994 (9th Cir. 2016). But Federal Rule of Civil Procedure 44.1 clarified that an interpretation of foreign law “must be treated as a ruling on a question of law.” Accordingly, like any legal issue, “the court may consider any relevant material or source, including testimony, whether or not submitted by a party or admissible under the

2 Contrary to Shon ’s argument , w e did not direct the district court to hold a hearing on the limited remand

. Even if t h e district court wrongly interpreted our order as forbidding an evidentiary hearing, we did not require one. Nor was one needed when the existing evidence already sufficiently addressed the factual issues identified in our limited remand order

. Thus, any error would have been harmless.R ADU V

. S HON 15

Federal Rules of Evidence.” Fed. R. Civ. P. 44 .1. Moreover, “the court is not limited by material presented by the parties; it may engage in its own research and consider any relevant material thus found.” Fed. R. Civ. P. 44.1 advisory committee’s note to 1966 amendment. That said, “expert testimon y accompanied by extracts from foreign legal materials has been and will likely continue to be the basic mode of proving foreign law.” Universe Sales Co., Ltd. v. Silver Castle, Ltd. , 182 F.3d 1036, 1038 (9th Cir. 1999).

Courts nonetheless have an “inde pendent obligation to adequately ascertain relevant foreign law, even if the parties’ submissions are lacking.” de Fontbrune , 838 F.3d at 997. Though international comity requires American courts to “carefully consider a foreign state’s views about the m eaning of its own laws,” that deference has its limits. Animal Sci. Prods., Inc. v. Hebei Welcome Pharm. Co. , 138 S. Ct. 1865, 1873 (2018). “The appropriate weight in each case

. . . will depend upon the circumstances; a federal court is neither bound to adopt the foreign government’s characterization nor required to ignore other relevant materials.” Id.

U nderstanding the laws and procedures of a nother country can be difficult

— especially when trying to make such determinations expediently

, as the Convention directs

. A nd t he State Department and foreign Central Authorities

are proper and useful resources when evaluating a foreign legal landscape

. See Convention Art. 7

. A sister circuit, for instance, has directed a district court “to make any appropriate or necessary inquiries of the [foreign government]

. . . and to do so, inter alia , by requesting the aid of the United States Department of State, which can communicate directly with that foreign government.” Blondin v. Dubois , 189 F.3d 240, 249 (2d Cir. 1999). Indeed, we contemplated the district court ’s ability to seek16 R ADU V

. S HON

assistance f rom the State Department when we remanded the first return order

. See Radu I , 11 F.4th at 109 0

– 9 1.

Shon does not contest any foreign legal conclusion but challenges the methods the court used to determine German procedural issues. Though a legal conclusion on foreign law is reviewed de novo, see de Fontbrune , 838 F.3d at 1000, we have indicated that a district court’s selection of methods to evaluate foreign law is discretion ary

. See Tobar v. United States , 639 F.3d 1191, 1200 (9th Cir. 2011) ( noting that the district court could “inquire further into the content of Ecuadorian law” “in its discretion” ). Accordingly, we review the district court’s methods of foreign law research for abuse of discretion. This deferential standard is necessary to preserve the flexibility that Rule 44.1 affords courts to research foreign law

. A nd our de novo review of the ultimate legal conclusion ensures that foreign l egal issues

are treated like domestic ones.
The district court neither abused its discretion nor violated Shon’s due process rights by communicating with the State Department and, through it, the German Central Authority

. “ [I] ndependent judicial research” on a legal question “does not implicate the judicial notice and ex parte issues spawned by independent factual research.” de Fontbrune , 838 F.3d at 999 ; see also G&G Pro ds. LLC v. Rusic , 902 F.3d 940, 94 8 (9th Cir. 2018) ( “formal notice” of court’s intent to research foreign law not required)

. Nor do the Federal Rules of Evidence and its hearsay rules apply to foreign law materials, much as legal research on domestic law cannot trigger evidentiary objections. See de Fontbrune

, 838 F.3d at 999.

Of c ourse, “both trial and appellate courts are urged to research and analyze foreign law independently

, ” Twohy v.R ADU V

. S HON 17

First Nat. Bank of Chi

. , 758 F.2d 1185, 1193 (7th Cir. 1985) ;

see also de Fontbrune , 838 F.3d at 997 , and with due consideration for the parties’ submissions. But here, the district court did not view it self bound by information received from the State Department; it properly considered and weighed that information alongside the testimony of the parties and Shon’s expert. Shon

— who does not challenge any of the legal conclusions that the district court reached

— fails to persuade that the district court ab used its discretion in the way it reached them.

C Finally, Shon challenged several factual findings underlying the district court’s third return order and asserted that the law

- of

- the

- case doctrine prohibited the court from revisiting its grave

- risk finding

. We review factual findings for clear error

, which occurs if “the finding is illogical, implausible, or without support in inferences that may be drawn from the facts in the record.” Doe v. Snyder , 28 F.4th 103, 106 (9th Cir. 2022) (internal quotation marks and citation omitted)

. “ While a district court has no ob ligation under the Convention to consider ameliorative measures that have not been raised by the parties, it ordinarily should address ameliorative measures raised by the parties or obviously suggested by the circumstances of the case

. . . . ” Golan , 142 S. Ct. at 1893. On remand, t he district court clarified that the minor children would be at a grave risk of psychological harm only if they return ed to Germany and remain ed in Radu’s sole custody for years due to the cumulative nature of psychologi cal harm

. Radu

, 2023 WL 142908, at *2. If Shon could not remain in Germany past the expiration of her tourist visa (around ninety days) , then the court found no18 R ADU V

. S HON

issue with Radu taking physical custody of the children for a short time until the final custody determination is made by German authorities

. Id. Because no exception to return would apply under those circumstances , the court ordered the children’s return. Many of the specific findings that Shon first challenged

— such as the enforceability of sole custody as an ameliorative measure and her parents’ willingness to travel to Germany

— ar e immaterial under the clarified return order

, which does not rely on these facts. As to the findings that remain at issue , the record provides adequate support. See Landis v. Wash. State Major League Baseball Stadium Pub. Facilities Dist. , 11 F.4th 1101, 1105 (9th Cir. 2021) (“This is deferential review; we reverse only if we are left with a definite and firm conviction tha t a mistake has been committed.” ( internal quotation marks and citation omitted)).
First, the record supports the district court’s determination that the time frame in which a German court would determine custody would be a few months rather than
years . T he district court found that a merits decision would be made within months. Radu , 2023 WL 142908, at * 2

. Shon’s German law expert’s testimony supports this finding

. He testified that a German court would likely require the children to live in Germany for up to six months before determining custody but that the court would also have discretion to make an earlier decision

. And the district court cited a German statute providing that the determination of custody i ssues “shall have priority” and “shall be handled in an expedited manner.” That the waiting period is likely to be months instead of years is supported by the record.R ADU V

. S HON 19

Second, the hearing testimony supports the court’s determination that Shon could return with the children. When asked during the hearing if she would accompany the children, Shon answered, “Of course.” She also said that she could take humanitarian leave of up to six months from her job with her manager’s approval . Although Shon ex pressed some financial concerns, the district court relied on other evidence, such as her employment, lifestyle, and ability to obtain her parents’ financial support. That the district court ordered Radu to pay for a separate household for Shon and the ch ildren, Radu , 2023 WL 142908, at *3, further minimizes these concerns. Shon ’s ability to remain in Germany until the final custody decision is no longer relevant : T he district court clarified that no grave risk arises if the children enter Radu’s physical custody for the remaining time.

Third

, based on the lack of any evidence or testimony about pending criminal charges in Germany, the court drew the supported inference that none existed. Finally, the law

- of

- the

- case doctrine did not prevent the district court from revisiting its prior ruling on grave risk

. “[T]he law

- of

- the

- cas e doctrine ‘merely expresses the practice of courts generally to refuse to reopen what has been decided, not a limit to their power.’” Christianson v. Colt Indus. Operating Corp. , 486 U.S. 800, 817 (1988) (quoting Messinger v. Anderson , 225 U.S. 436, 444 (1912 ) ). It “applies most clearly where an issue has been decided by a higher court

. ” Askins v. U.S. Dep ’t of Homeland Sec

. , 899 F.3d 1035, 1042 (9th Cir. 2018). W e did not decide th e grave

- risk issue in the first appeal because Radu did not challenge the district court’s finding

, but we noted that “ the facts here do seem to be a borderline case whether an Article 13(b) finding is warranted

. ” Radu I , 11 F.4th at 1089. Even20 R ADU V

. S HON

though the district court found grave risk in its first return order, it was free to revisit this ruling based on updated evidence about the likely time frame for German courts to decide the merits of the custody dispute

. See Radu , 2023 WL 142908, at *2. As we have discussed, Gaudin instructs district courts to decide whether grave risk exists based on
t he current circumstances. 415 F.3d at 1036

. IV The district court did not err in refusing to hold a new evidentiary hearing or in consulting the State Department. Adequate evidence supports the factual findings that Shon challenges. We thus affirm the district court’s grant of the petition for the ch ildren’s return with the ameliorative

measure s ordered by the district court

. 3

AFFIRMED.

3 Shon’s motion to stay the lower court action is denied as moot.R ADU V

. S HON 21

MURGUIA, Chief Judge, concurring:

I concur fully in the principal opinion. I write separately to express my view that, in Radu I , we should not have “decline[d] to allocate a burden of proof on the reasonableness of” an ameliorative measure. Radu v. Sho n , 11 F.4th 1080, 1089 (9th Cir. 2021) [ Radu I ], cert. granted, judgment vacated , 142 S. Ct. 2861 (2022). When we did so, we noted: “Congress is capable of assigning burdens of proof and has already done so under [the International Child Abduction Remedie s Act (“ICARA”)]. We need not add judicial constraints absent from ICARA or the [Hague Convention on the Civil Aspects of International Child Abduction (“Convention”)].” Id. (citation omitted). It is true that the Convention and ICARA provide that the petitioner has the burden to establish a prima facie case of wrongful removal. See Golan v. Saada , 142 S. Ct. 1880, 1888

– 89 (2022). And both the Convention and ICARA then shift the burden onto the respondent to prove that, if returned, the removed childr en would be subject to a grave risk of physical or psychological harm. See id. But neither the Convention nor ICARA mentions measures that could ameliorate such a grave risk. Id. at 1892. Rather, ameliorative measures are a “judicial construct.” Danai pour v. McLarey , 286 F.3d 1, 21 (1st Cir. 2002) (citation omitted).
After further consideration, I now believe that when a petitioner proffers a measure to ameliorate the grave risk of harm, it should be the petitioner’s burden to establish that the

meas ure is reasonably appropriate and effective. Three of our sister circuits have adopted this view, and we should have adopted it in Radu I

. See Simcox v. Simcox , 511 F.3d 594, 611 (6th Cir. 2007); Acosta v. Acosta , 725 F.3d 868, 877 (8th Cir. 2013); Danai pour , 286 F.3d at 21. Placing this22 R ADU V

. S HON

burden on the petitioner does not preclude district courts from considering, on their own, potential ameliorative measures not raised by the parties that are “obviously suggested by the circumstances of the case.” Golan , 142 S. Ct. at 1893. It only assists district courts’ decisionmaking and guides their discretion as to the measures raised by a petitioner seeking to mitigate a grave risk of harm. This issue is no longer squarely presented in this case, and accordingly, we cannot resolve it. But because the Supreme Court vacated Radu I in light of Golan , a future panel may

— and, in my view, should

— properly allocate the burden of proof in an appropriate case.