diff --git a/system/blueprints/user/account.yaml b/system/blueprints/user/account.yaml
index b5cde9bcd..b48e79007 100644
--- a/system/blueprints/user/account.yaml
+++ b/system/blueprints/user/account.yaml
@@ -126,3 +126,4 @@ form:
                     ignore_empty: true
                     validate:
                         type: array
+                        value_type: bool
diff --git a/system/blueprints/user/group.yaml b/system/blueprints/user/group.yaml
index ddb7d242c..3ab07546f 100644
--- a/system/blueprints/user/group.yaml
+++ b/system/blueprints/user/group.yaml
@@ -45,3 +45,4 @@ form:
             ignore_empty: true
             validate:
                 type: array
+                value_type: bool
diff --git a/system/src/Grav/Common/Data/Validation.php b/system/src/Grav/Common/Data/Validation.php
index 30666dbf9..2764067fa 100644
--- a/system/src/Grav/Common/Data/Validation.php
+++ b/system/src/Grav/Common/Data/Validation.php
@@ -720,7 +720,13 @@ class Validation
                 if ($type && $val !== '' && $val !== null) {
                     switch ($type) {
                         case 'bool':
-                            $val = Utils::isPositive($val);
+                            if (Utils::isPositive($val)) {
+                                $val = true;
+                            } elseif (Utils::isNegative($val)) {
+                                $val = false;
+                            } else {
+                                $val = null;
+                            }
                             break;
                         case 'int':
                             $val = (int)$val;