diff --git a/QueryKit.UnitTests/FilterParsingRegressionTests.cs b/QueryKit.UnitTests/FilterParsingRegressionTests.cs
index d6c67b3..ffd4f0b 100644
--- a/QueryKit.UnitTests/FilterParsingRegressionTests.cs
+++ b/QueryKit.UnitTests/FilterParsingRegressionTests.cs
@@ -261,26 +261,6 @@ public void comparison_operator_factory_has_one_test_case_per_operator_type()
         ComparisonOperatorFactories().Should().HaveCount(24);
     }
 
-    [Theory]
-    [InlineData(false, new[] { "lamb" })]
-    [InlineData(true, new[] { "null", "other" })]
-    public void case_insensitive_in_operator_factory_reads_a_constant_list(bool notIn, string[] expectedFirstNames)
-    {
-        var people = new[]
-        {
-            new TestingPerson { Title = null, FirstName = "null" },
-            new TestingPerson { Title = "Lamb", FirstName = "lamb" },
-            new TestingPerson { Title = "other", FirstName = "other" },
-        };
-        Expression<Func<TestingPerson, string?>> title = x => x.Title;
-        var comparisonOperator = notIn ? ComparisonOperator.NotInOperator(true) : ComparisonOperator.InOperator(true);
-
-        var body = comparisonOperator.GetExpression<TestingPerson>(title.Body, Expression.Constant(new List<string> { "LAMB" }), null);
-        var filterExpression = Expression.Lambda<Func<TestingPerson, bool>>(body, title.Parameters);
-
-        people.AsQueryable().Where(filterExpression).Select(x => x.FirstName).Should().Equal(expectedFirstNames);
-    }
-
     [Fact]
     public void comparison_operator_factory_with_uses_all_builds_all_expression()
     {
diff --git a/QueryKit/Operators/ComparisonOperator.cs b/QueryKit/Operators/ComparisonOperator.cs
index ad8e760..2e01b40 100644
--- a/QueryKit/Operators/ComparisonOperator.cs
+++ b/QueryKit/Operators/ComparisonOperator.cs
@@ -618,8 +618,7 @@ public override Expression GetExpression<T>(Expression left, Expression right, T
                 var listType = typeof(List<string>);
                 var caseList = Activator.CreateInstance(listType);
 
-                // A caller can pass the list as a constant, like v1.14.2.
-                var originalList = (values ?? ((ConstantExpression)right).Value) as IEnumerable<string>;
+                var originalList = values as IEnumerable<string>;
                 foreach (var value in originalList!)
                 {
                     listType.GetMethod("Add")!.Invoke(caseList, new[] { caseMode == CaseInsensitiveMode.Upper ? value.ToUpper() : value.ToLower() });
@@ -864,8 +863,7 @@ public override Expression GetExpression<T>(Expression left, Expression right, T
                 var listType = typeof(List<string>);
                 var caseList = Activator.CreateInstance(listType);
 
-                // A caller can pass the list as a constant, like v1.14.2.
-                var originalList = (values ?? ((ConstantExpression)right).Value) as IEnumerable<string>;
+                var originalList = values as IEnumerable<string>;
                 foreach (var value in originalList!)
                 {
                     listType.GetMethod("Add")!.Invoke(caseList, new[] { caseMode == CaseInsensitiveMode.Upper ? value.ToUpper() : value.ToLower() });