diff --git a/backend/hansard-search/internal/adapter/sqlitefile/index_downloader.go b/backend/hansard-search/internal/adapter/sqlitefile/index_downloader.go
index 8f3e3671..61c16083 100644
--- a/backend/hansard-search/internal/adapter/sqlitefile/index_downloader.go
+++ b/backend/hansard-search/internal/adapter/sqlitefile/index_downloader.go
@@ -31,8 +31,9 @@ type s3Downloader interface {
 
 // IndexDownloader downloads and validates the hansard SQLite search index from S3.
 type IndexDownloader struct {
-	s3     s3Downloader
-	bucket string
+	s3        s3Downloader
+	bucket    string
+	localPath string
 }
 
 // NewIndexDownloaderFromEnv constructs an IndexDownloader from environment variables.
@@ -51,7 +52,7 @@ func NewIndexDownloaderFromEnv(ctx context.Context) (*IndexDownloader, error) {
 
 // NewIndexDownloader constructs an IndexDownloader from explicit dependencies (for testing).
 func NewIndexDownloader(s3Client s3Downloader, bucket string) *IndexDownloader {
-	return &IndexDownloader{s3: s3Client, bucket: bucket}
+	return &IndexDownloader{s3: s3Client, bucket: bucket, localPath: localIndexPath}
 }
 
 // Download fetches s3://bucket/sqliteKey to /tmp/index.sqlite using streaming I/O,
@@ -67,7 +68,7 @@ func (d *IndexDownloader) Download(ctx context.Context, sqliteKey, expectedSHA25
 	}
 	defer out.Body.Close()
 
-	f, err := os.Create(localIndexPath)
+	f, err := os.Create(d.localPath)
 	if err != nil {
 		return "", fmt.Errorf("create local index file: %w", err)
 	}
@@ -86,11 +87,11 @@ func (d *IndexDownloader) Download(ctx context.Context, sqliteKey, expectedSHA25
 		return "", usecase.ErrChecksumMismatch
 	}
 
-	if err := verifySchemaVersion(localIndexPath); err != nil {
+	if err := verifySchemaVersion(d.localPath); err != nil {
 		return "", err
 	}
 
-	return localIndexPath, nil
+	return d.localPath, nil
 }
 
 func verifySchemaVersion(path string) error {
diff --git a/backend/hansard-search/internal/adapter/sqlitefile/index_downloader_test.go b/backend/hansard-search/internal/adapter/sqlitefile/index_downloader_test.go
index dd61870a..826966ee 100644
--- a/backend/hansard-search/internal/adapter/sqlitefile/index_downloader_test.go
+++ b/backend/hansard-search/internal/adapter/sqlitefile/index_downloader_test.go
@@ -71,19 +71,18 @@ func sha256hex(data []byte) string {
 
 func TestIndexDownloader_HappyPath(t *testing.T) {
 	_, content := createTestDB(t, "v1")
+	localPath := filepath.Join(t.TempDir(), "index.sqlite")
 
 	expectedHash := sha256hex(content)
 	mock := &mockS3Downloader{body: content}
 
-	// Override localIndexPath to write to a temp location.
-	// The downloader writes to /tmp/index.sqlite; in tests we accept this.
-	d := &IndexDownloader{s3: mock, bucket: "test-bucket"}
+	d := &IndexDownloader{s3: mock, bucket: "test-bucket", localPath: localPath}
 	got, err := d.Download(context.Background(), "some/key", expectedHash)
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
-	if got != localIndexPath {
-		t.Errorf("want %q, got %q", localIndexPath, got)
+	if got != localPath {
+		t.Errorf("want %q, got %q", localPath, got)
 	}
 }
 
@@ -91,7 +90,7 @@ func TestIndexDownloader_ChecksumMismatch(t *testing.T) {
 	_, content := createTestDB(t, "v1")
 
 	mock := &mockS3Downloader{body: content}
-	d := &IndexDownloader{s3: mock, bucket: "test-bucket"}
+	d := &IndexDownloader{s3: mock, bucket: "test-bucket", localPath: filepath.Join(t.TempDir(), "index.sqlite")}
 
 	_, err := d.Download(context.Background(), "some/key", "deadbeef")
 	if !errors.Is(err, usecase.ErrChecksumMismatch) {
@@ -104,7 +103,7 @@ func TestIndexDownloader_SchemaMismatch(t *testing.T) {
 
 	expectedHash := sha256hex(content)
 	mock := &mockS3Downloader{body: content}
-	d := &IndexDownloader{s3: mock, bucket: "test-bucket"}
+	d := &IndexDownloader{s3: mock, bucket: "test-bucket", localPath: filepath.Join(t.TempDir(), "index.sqlite")}
 
 	_, err := d.Download(context.Background(), "some/key", expectedHash)
 	if !errors.Is(err, usecase.ErrSchemaMismatch) {