diff --git a/changelog.d/evaluate-condition-fail-closed.fixed.md b/changelog.d/evaluate-condition-fail-closed.fixed.md
new file mode 100644
index 000000000..d173dead0
--- /dev/null
+++ b/changelog.d/evaluate-condition-fail-closed.fixed.md
@@ -0,0 +1 @@
+- Unevaluable validation `condition` / `unless` expressions now throw `Wheels.InvalidValidationCondition` even when `showErrorInformation` is false, instead of silently skipping the validation (#3398)
diff --git a/vendor/wheels/model/validations.cfc b/vendor/wheels/model/validations.cfc
index b1dffdeba..054af72a0 100644
--- a/vendor/wheels/model/validations.cfc
+++ b/vendor/wheels/model/validations.cfc
@@ -580,19 +580,14 @@ component {
 				try {
 					local[local.key] = $evaluateConditionString(arguments[local.item]);
 				} catch (any e) {
-					if ($get("showErrorInformation")) {
-						Throw(
-							type = "Wheels.InvalidValidationCondition",
-							message = "The `#local.item#` expression `#arguments[local.item]#` could not be evaluated: #e.message#",
-							extendedInfo = "Supported forms: `this.property`, `this.method()` (with named `key='val'` or positional `'val'` arguments), bare `method()` (optionally negated with `!`), and binary comparisons using eq/neq/lt/lte/gt/gte or ==/!=/</<=/>/>=."
-						);
-					}
-					cflog(
-						text = "Wheels: validation `#local.item#` expression `#arguments[local.item]#` could not be evaluated (#e.message#); validation skipped.",
-						type = "error",
-						file = "wheels-errors"
+					// Fail closed regardless of showErrorInformation. Returning
+					// false here means "skip this validation" ($validate), which
+					// is fail-open for a broken condition/unless expression.
+					Throw(
+						type = "Wheels.InvalidValidationCondition",
+						message = "The `#local.item#` expression `#arguments[local.item]#` could not be evaluated: #e.message#",
+						extendedInfo = "Supported forms: `this.property`, `this.method()` (with named `key='val'` or positional `'val'` arguments), bare `method()` (optionally negated with `!`), and binary comparisons using eq/neq/lt/lte/gt/gte or ==/!=/</<=/>/>=."
 					);
-					return false;
 				}
 			}
 		}
diff --git a/vendor/wheels/tests/specs/model/validationsSpec.cfc b/vendor/wheels/tests/specs/model/validationsSpec.cfc
index 1d9684313..bb294acb4 100644
--- a/vendor/wheels/tests/specs/model/validationsSpec.cfc
+++ b/vendor/wheels/tests/specs/model/validationsSpec.cfc
@@ -310,13 +310,34 @@ component extends="wheels.WheelsTest" {
 				expect(callValid).toThrow("Wheels.InvalidValidationCondition")
 			})
 
-			it("skips the validation without throwing in production when a condition cannot be evaluated", () => {
+			// M1: $evaluateCondition must fail closed when the expression cannot
+			// be evaluated. Returning false here means "skip this validation"
+			// ($validate: if ($evaluateCondition(...))), which is fail-open.
+			it("throws when a condition cannot be evaluated even if showErrorInformation is false", () => {
 				args.condition = "noSuchMethod()"
 				user.validatesLengthOf(argumentCollection = args)
 				var originalShowErrorInformation = application.wheels.showErrorInformation
 				try {
 					application.wheels.showErrorInformation = false
-					expect(user.valid()).toBeTrue()
+					var callValid = () => {
+						user.valid()
+					}
+					expect(callValid).toThrow("Wheels.InvalidValidationCondition")
+				} finally {
+					application.wheels.showErrorInformation = originalShowErrorInformation
+				}
+			})
+
+			it("throws when an unless expression cannot be evaluated even if showErrorInformation is false", () => {
+				args.unless = "noSuchMethod()"
+				user.validatesLengthOf(argumentCollection = args)
+				var originalShowErrorInformation = application.wheels.showErrorInformation
+				try {
+					application.wheels.showErrorInformation = false
+					var callValid = () => {
+						user.valid()
+					}
+					expect(callValid).toThrow("Wheels.InvalidValidationCondition")
 				} finally {
 					application.wheels.showErrorInformation = originalShowErrorInformation
 				}