Daniel J. Hennessy, Jr. v. Wells Fargo Bank, N.A., 968 N.W.2d 684

Daniel and Jane Hennessy borrowed $7.5 million from Wells Fargo to build a condominium in San José del Cabo, Mexico; the transaction involved a loan agreement, promissory note (Wisconsin law, English), and a trust agreement (Mexican law, Spanish) securing the property.
The Hennessys defaulted and Wells Fargo sued in Mexico; the Mexican district court entered judgment and the Mexican appellate court affirmed in part, awarding Wells Fargo US$7,500,000 (to be converted to pesos), interest, fees, costs, and permitting seizure/auction of the collateral and potential recovery of any deficiency.
The Hennessys sued in Milwaukee seeking a declaratory judgment that a Wisconsin breach claim was time-barred; Wells Fargo counterclaimed to domesticate the Mexican judgment in Wisconsin.
The circuit court held two hearings: (1) as a factfinder on Mexican law (crediting Wells Fargo’s Mexican-law expert) and concluded the Mexican judgment created personal money liability (including a possible deficiency); (2) exercised discretion under comity to domesticate the judgment and enter it in Wisconsin.
The court of appeals affirmed; the Wisconsin Supreme Court (1) reaffirmed that foreign law is a question of fact (Wis. Stat. §902.02(5)), (2) found the circuit court’s interpretation of Mexican law not clearly erroneous, and (3) held domestication under comity was a proper discretionary exercise.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Proper standard of review for foreign law	Hennessy: treat foreign law as a question of law and review de novo	Wells Fargo: maintain Wisconsin practice treating foreign law as a question of fact	Court: reaffirmed foreign law is a question of fact; appellate review is for clear error; declined to change standard (statutory and stare-decisis grounds).
Scope of Mexican judgment (in rem vs. in personam; deficiency)	Hennessy: Mexican proceedings were in rem (foreclosure) only; no personal money judgment/deficiency allowed	Wells Fargo: judgment expressly awards $7.5M, interest, fees and permits collateral transfer and enforcement of any deficiency	Court: credited Wells Fargo’s expert; held Mexican judgment allowed personal money recovery and pursuit of deficiency; circuit court not clearly erroneous.
Domestication under comity / finality / "sum certain"	Hennessy: judgment lacks a single sum certain because interest, fees, commissions, and deficiency require further computation; therefore not final for domestication	Wells Fargo: judgment is final and enforceable; further calculations are execution/enforcement, not reopening merits	Court: domesticating judgment was reasonable under comity; circuit court did not err in discretion; judgment was final enough to recognize and domesticate.

Animal Sci. Prods., Inc. v. Hebei Welcome Pharm. Co. Ltd., 138 S. Ct. 1865 (U.S. 2018) (discussing treatment and appellate review of foreign law under federal procedure)
Hilton v. Guyot, 159 U.S. 113 (U.S. 1895) (comity doctrine: courts should not relitigate merits of foreign judgments)
Royster-Clark, Inc. v. Olsen's Mill, Inc., 290 Wis. 2d 264 (Wis. 2006) (deference to circuit court findings of fact; clear-error standard)
Milwaukee Cheese Co. v. Olafsson, 40 Wis. 2d 575 (Wis. 1968) (foreign law must be pleaded and proved as a fact)
Ingersoll Milling Mach. Co. v. Granger, 833 F.2d 680 (7th Cir. 1987) (foreign-money-judgment recognition can be proper even where additional computations of interest or currency conversion are needed)