diff --git a/lib/class-wp-theme-json-gutenberg.php b/lib/class-wp-theme-json-gutenberg.php
index 8c2857fa89d0c..b2b3fa997b8cd 100644
--- a/lib/class-wp-theme-json-gutenberg.php
+++ b/lib/class-wp-theme-json-gutenberg.php
@@ -3389,7 +3389,7 @@ public function set_spacing_sizes() {
 			|| ! is_numeric( $spacing_scale['mediumStep'] )
 			|| ( '+' !== $spacing_scale['operator'] && '*' !== $spacing_scale['operator'] ) ) {
 			if ( ! empty( $spacing_scale ) ) {
-				trigger_error( __( 'Some of the theme.json settings.spacing.spacingScale values are invalid', 'gutenberg' ), E_USER_NOTICE );
+				_doing_it_wrong( __METHOD__, __( 'Some of the theme.json settings.spacing.spacingScale values are invalid', 'gutenberg' ), '6.1.0' );
 			}
 			return null;
 		}
diff --git a/phpunit/class-wp-theme-json-test.php b/phpunit/class-wp-theme-json-test.php
index 0e212983d9080..35747a290ca74 100644
--- a/phpunit/class-wp-theme-json-test.php
+++ b/phpunit/class-wp-theme-json-test.php
@@ -1282,8 +1282,7 @@ public function data_generate_spacing_scale_fixtures() {
 	 * @dataProvider data_set_spacing_sizes_when_invalid
 	 */
 	public function test_set_spacing_sizes_when_invalid( $spacing_scale, $expected_output ) {
-		$this->expectNotice();
-		$this->expectNoticeMessage( 'Some of the theme.json settings.spacing.spacingScale values are invalid' );
+		$this->setExpectedIncorrectUsage( 'WP_Theme_JSON_Gutenberg::set_spacing_sizes' );
 
 		$theme_json = new WP_Theme_JSON_Gutenberg(
 			array(