diff --git a/oslo_policy/shell.py b/oslo_policy/shell.py
index 222ab6a9..fe143fb4 100644
--- a/oslo_policy/shell.py
+++ b/oslo_policy/shell.py
@@ -14,6 +14,7 @@
 # limitations under the License.
 
 import argparse
+import collections
 import sys
 
 from oslo_serialization import jsonutils
@@ -33,7 +34,25 @@ def _try_rule(key, rule, target, access_data, o):
         print("exception: %s" % rule)
 
 
-def tool(policy_file, access_file, apply_rule, is_admin=False):
+def flatten(d, parent_key=''):
+    """Flatten a nested dictionary
+
+    Converts a dictionary with nested values to a single level flat
+    dictionary, with dotted notation for each key.
+
+    """
+    items = []
+    for k, v in d.items():
+        new_key = parent_key + '.' + k if parent_key else k
+        if isinstance(v, collections.MutableMapping):
+            items.extend(flatten(v, new_key).items())
+        else:
+            items.append((new_key, v))
+    return dict(items)
+
+
+def tool(policy_file, access_file, apply_rule, is_admin=False,
+         target_file=None):
     access = access_file.read()
     access_data = jsonutils.loads(access)['token']
     access_data['roles'] = [role['name'] for role in access_data['roles']]
@@ -47,16 +66,20 @@ def tool(policy_file, access_file, apply_rule, is_admin=False):
     o = Object()
     o.rules = rules
 
-    target = {"project_id": access_data['project_id']}
+    if target_file:
+        target = target_file.read()
+        target_data = flatten(jsonutils.loads(target))
+    else:
+        target_data = {"project_id": access_data['project_id']}
 
     if apply_rule:
         key = apply_rule
         rule = rules[apply_rule]
-        _try_rule(key, rule, target, access_data, o)
+        _try_rule(key, rule, target_data, access_data, o)
         return
     for key, rule in rules.items():
         if ":" in key:
-            _try_rule(key, rule, target, access_data, o)
+            _try_rule(key, rule, target_data, access_data, o)
 
 
 def main():
@@ -72,6 +95,11 @@ def main():
         type=argparse.FileType('rb', 0),
         help='path to a file containing OpenStack Identity API' +
         ' access info in JSON format')
+    parser.add_argument(
+        '--target',
+        type=argparse.FileType('rb', 0),
+        help='path to a file containing custom target info in' +
+        ' JSON format. This will be used to evaluate the policy with.')
     parser.add_argument(
         '--rule',
         help='rule to test')
@@ -85,7 +113,7 @@ def main():
         is_admin = args.is_admin.lower() == "true"
     except Exception:
         is_admin = False
-    tool(args.policy, args.access, args.rule, is_admin)
+    tool(args.policy, args.access, args.rule, is_admin, args.target)
 
 
 if __name__ == "__main__":
diff --git a/oslo_policy/tests/test_shell.py b/oslo_policy/tests/test_shell.py
index 70fa407c..97c64c81 100644
--- a/oslo_policy/tests/test_shell.py
+++ b/oslo_policy/tests/test_shell.py
@@ -62,6 +62,39 @@ class CheckerTestCase(base.PolicyBaseTestCase):
 '''
         self.assertEqual(expected, stdout.getvalue())
 
+    @mock.patch("oslo_policy._checks.TrueCheck.__call__")
+    def test_pass_rule_parameters_with_custom_target(self, call_mock):
+        apply_rule = None
+        is_admin = False
+        access_data = token_fixture.SCOPED_TOKEN_FIXTURE["token"]
+        access_data['roles'] = [
+            role['name'] for role in access_data['roles']]
+        access_data['project_id'] = access_data['project']['id']
+        access_data['is_admin'] = is_admin
+
+        sample_target = {
+            "project_id": access_data["project"]["id"],
+            "domain_id": access_data["project"]["domain"]["id"]
+        }
+        self.create_config_file(
+            "target.json",
+            jsonutils.dumps(sample_target))
+
+        policy_file = open(self.get_config_file_fullname('policy.yaml'), 'r')
+        access_file = open(self.get_config_file_fullname('access.json'), 'r')
+        target_file = open(self.get_config_file_fullname('target.json'), 'r')
+        stdout = self._capture_stdout()
+
+        shell.tool(policy_file, access_file, apply_rule, is_admin,
+                   target_file)
+        call_mock.assert_called_once_with(
+            sample_target, access_data, mock.ANY,
+            current_rule="sampleservice:sample_rule")
+
+        expected = '''passed: sampleservice:sample_rule
+'''
+        self.assertEqual(expected, stdout.getvalue())
+
     def test_all_nonadmin(self):
 
         policy_file = open(self.get_config_file_fullname('policy.yaml'), 'r')
@@ -75,3 +108,30 @@ class CheckerTestCase(base.PolicyBaseTestCase):
         expected = '''passed: sampleservice:sample_rule
 '''
         self.assertEqual(expected, stdout.getvalue())
+
+    def test_flatten_from_dict(self):
+        target = {
+            "target": {
+                "secret": {
+                    "project_id": "1234"
+                }
+            }
+        }
+        result = shell.flatten(target)
+        self.assertEqual(result, {"target.secret.project_id": "1234"})
+
+    def test_flatten_from_file(self):
+        target = {
+            "target": {
+                "secret": {
+                    "project_id": "1234"
+                }
+            }
+        }
+        self.create_config_file(
+            "target.json",
+            jsonutils.dumps(target))
+        target_file = open(self.get_config_file_fullname('target.json'), 'r')
+        target_from_file = target_file.read()
+        result = shell.flatten(jsonutils.loads(target_from_file))
+        self.assertEqual(result, {"target.secret.project_id": "1234"})
diff --git a/releasenotes/notes/Pass-target-dict-to-oslopolicy-checker-87185d40aec413ee.yaml b/releasenotes/notes/Pass-target-dict-to-oslopolicy-checker-87185d40aec413ee.yaml
new file mode 100644
index 00000000..a844f3f0
--- /dev/null
+++ b/releasenotes/notes/Pass-target-dict-to-oslopolicy-checker-87185d40aec413ee.yaml
@@ -0,0 +1,6 @@
+---
+features:
+  - |
+    oslopolicy-checker was added the ability to accept a file containing a hash
+    that represents the target. This makes it possible to check policies that
+    have non-conventional targets such as barbican.