diff --git a/cpp/src/arrow/json/chunker.cc b/cpp/src/arrow/json/chunker.cc
index f69c45b93867..4bff06e2ca5c 100644
--- a/cpp/src/arrow/json/chunker.cc
+++ b/cpp/src/arrow/json/chunker.cc
@@ -42,17 +42,8 @@ int64_t ConsumeWhitespace(std::string_view view) {
   return static_cast<int64_t>(ws_count);
 }
 
-Status ConsumeDocument(simdjson::ondemand::document_stream::iterator& it) {
-  ARROW_ASSIGN_OR_RAISE(
-      auto document, internal::ResolveSimdjsonResult(*it, "Failed to get JSON document"));
-  ARROW_ASSIGN_OR_RAISE(
-      auto value,
-      internal::ResolveSimdjsonResult(document.get_value(), "Failed to get JSON value"));
-  return internal::ConsumeJsonValue(value);
-}
-
 // A BoundaryFinder implementation that assumes JSON objects can contain raw newlines,
-// and uses actual JSON parsing to delimit them.
+// and uses the structural indexes computed by simdjson to delimit them.
 class ParsingBoundaryFinder : public BoundaryFinder {
  public:
   explicit ParsingBoundaryFinder(MemoryPool* pool) : pool_(pool) {}
@@ -122,8 +113,8 @@ class ParsingBoundaryFinder : public BoundaryFinder {
   }
 
   // Find the first or last JSON object (depending on `find_last`)
-  // and return the consumed JSON byte length, or 0 if no valid document
-  // can be parsed.
+  // and return the consumed JSON byte length, or 0 if no complete document
+  // can be found.
   Result<size_t> FindDocument(simdjson::padded_string_view input, bool find_last) {
     simdjson::ondemand::document_stream stream;
     // XXX Should be pass a specific batch_size?
@@ -137,8 +128,8 @@ class ParsingBoundaryFinder : public BoundaryFinder {
 
     int64_t consumed_length = 0;
     if (!find_last) {
-      // Parsing the first document only.
-      if (!ConsumeDocument(it).ok()) {
+      // Delimiting the first document only.
+      if (it.error()) {
         // Could be either a partial document or invalid JSON, we'll let
         // followup chunker or parser calls decide.
         return 0;
@@ -148,7 +139,7 @@ class ParsingBoundaryFinder : public BoundaryFinder {
       consumed_length = it.current_index() + it.source().size();
     } else {
       while (it != stream.end()) {
-        if (!ConsumeDocument(it).ok()) {
+        if (it.error()) {
           // Could be either a partial document or invalid JSON, we'll let
           // followup chunker or parser calls decide.
           break;
diff --git a/cpp/src/arrow/json/reader_test.cc b/cpp/src/arrow/json/reader_test.cc
index 7dcd30a0eb0b..549a49480579 100644
--- a/cpp/src/arrow/json/reader_test.cc
+++ b/cpp/src/arrow/json/reader_test.cc
@@ -743,16 +743,9 @@ TEST_P(StreamingReaderTest, PropagateErrorsNonLinewiseChunker) {
   read_options_.block_size = 10;
   parse_options_.newlines_in_values = true;
 
-  ASSERT_OK_AND_ASSIGN(reader, MakeReader(bad_first_block));
-  AssertReadNext(reader, &batch);
-  EXPECT_EQ(reader->bytes_processed(), 7);
-  ASSERT_BATCHES_EQUAL(*RecordBatchFromJSON(test_schema, "[{\"i\":0}]"), *batch);
-
   EXPECT_RAISES_WITH_MESSAGE_THAT(Invalid,
                                   ::testing::StartsWith("Invalid: JSON parse error"),
-                                  reader->ReadNext(&batch));
-  EXPECT_EQ(reader->bytes_processed(), 7);
-  AssertReadEnd(reader);
+                                  MakeReader(bad_first_block));
 
   ASSERT_OK_AND_ASSIGN(reader, MakeReader(bad_middle_blocks));
   AssertReadNext(reader, &batch);