diff --git a/stacktach/dbapi.py b/stacktach/dbapi.py
index 6488bfd..98003a8 100644
--- a/stacktach/dbapi.py
+++ b/stacktach/dbapi.py
@@ -2,6 +2,7 @@ import decimal
 import functools
 import json
 
+from django.db.models import FieldDoesNotExist
 from django.forms.models import model_to_dict
 from django.http import HttpResponse
 from django.http import HttpResponseBadRequest
@@ -51,7 +52,7 @@ def api_call(func):
 
 @api_call
 def list_usage_launches(request):
-    filter_args = _get_filter_args(request)
+    filter_args = _get_filter_args(models.InstanceUsage, request)
 
     if len(filter_args) > 0:
         objects = models.InstanceUsage.objects.filter(**filter_args)
@@ -69,7 +70,7 @@ def get_usage_launch(request, launch_id):
 
 @api_call
 def list_usage_deletes(request):
-    filter_args = _get_filter_args(request)
+    filter_args = _get_filter_args(models.InstanceDeletes, request)
 
     if len(filter_args) > 0:
         objects = models.InstanceDeletes.objects.filter(**filter_args)
@@ -87,7 +88,7 @@ def get_usage_delete(request, delete_id):
 
 @api_call
 def list_usage_exists(request):
-    filter_args = _get_filter_args(request)
+    filter_args = _get_filter_args(models.InstanceExists, request)
 
     if len(filter_args) > 0:
         objects = models.InstanceExists.objects.filter(**filter_args)
@@ -109,7 +110,15 @@ def _get_model_by_id(klass, model_id):
     return model_dict
 
 
-def _get_filter_args(request):
+def _check_has_field(klass, field_name):
+    try:
+        klass._meta.get_field_by_name(field_name)
+    except FieldDoesNotExist:
+        msg = "No such field '%s'." % field_name
+        raise BadRequestException(msg)
+
+
+def _get_filter_args(klass, request):
     filter_args = {}
     if 'instance' in request.GET:
         filter_args['instance'] = request.GET['instance']
@@ -118,6 +127,7 @@ def _get_filter_args(request):
 
             if key.endswith('_min'):
                 k = key[0:-4]
+                _check_has_field(klass, k)
                 try:
                     filter_args['%s__gte' % k] = utils.str_time_to_unix(value)
                 except AttributeError:
@@ -125,6 +135,7 @@ def _get_filter_args(request):
                     raise BadRequestException(message=msg)
             elif key.endswith('_max'):
                 k = key[0:-4]
+                _check_has_field(klass, k)
                 try:
                     filter_args['%s__lte' % k] = utils.str_time_to_unix(value)
                 except AttributeError:
diff --git a/tests/unit/test_dbapi.py b/tests/unit/test_dbapi.py
index 9e97502..8d18e08 100644
--- a/tests/unit/test_dbapi.py
+++ b/tests/unit/test_dbapi.py
@@ -1,6 +1,7 @@
 import datetime
 import unittest
 
+from django.db.models import FieldDoesNotExist
 import mox
 
 from stacktach import dbapi
@@ -15,18 +16,27 @@ class StacktachRawParsingTestCase(unittest.TestCase):
     def tearDown(self):
         self.mox.UnsetStubs()
 
+    def make_fake_model(self):
+        fake_model = self.mox.CreateMockAnything()
+        fake_meta = self.mox.CreateMockAnything()
+        fake_model._meta = fake_meta
+        return fake_model
+
     def test_get_filter_args(self):
         start_time = datetime.datetime.utcnow()
         start_decimal = utils.decimal_utc(start_time)
         end_time = start_time + datetime.timedelta(days=1)
         end_decimal = utils.decimal_utc(end_time)
         fake_request = self.mox.CreateMockAnything()
+        fake_model = self.make_fake_model()
+        fake_model._meta.get_field_by_name('launched_at')
+        fake_model._meta.get_field_by_name('launched_at')
         fake_request.GET = {'instance': INSTANCE_ID_1,
                             'launched_at_min': str(start_time),
                             'launched_at_max': str(end_time)}
         self.mox.ReplayAll()
 
-        filter_args = dbapi._get_filter_args(fake_request)
+        filter_args = dbapi._get_filter_args(fake_model, fake_request)
 
         self.mox.VerifyAll()
         self.assertEquals(filter_args['instance'], INSTANCE_ID_1)
@@ -38,19 +48,37 @@ class StacktachRawParsingTestCase(unittest.TestCase):
     def test_get_filter_args_bad_min_value(self):
         fake_request = self.mox.CreateMockAnything()
         fake_request.GET = {'launched_at_min': 'obviouslybaddatetime'}
+        fake_model = self.make_fake_model()
+        fake_model._meta.get_field_by_name('launched_at')
         self.mox.ReplayAll()
 
         self.assertRaises(dbapi.BadRequestException, dbapi._get_filter_args,
-                          fake_request)
+                          fake_model, fake_request)
 
         self.mox.VerifyAll()
 
     def test_get_filter_args_bad_max_value(self):
         fake_request = self.mox.CreateMockAnything()
         fake_request.GET = {'launched_at_max': 'obviouslybaddatetime'}
+        fake_model = self.make_fake_model()
+        fake_model._meta.get_field_by_name('launched_at')
         self.mox.ReplayAll()
 
         self.assertRaises(dbapi.BadRequestException, dbapi._get_filter_args,
-                          fake_request)
+                          fake_model, fake_request)
+
+        self.mox.VerifyAll()
+
+    def test_get_filter_args_bad_range_key(self):
+        start_time = datetime.datetime.utcnow()
+        fake_request = self.mox.CreateMockAnything()
+        fake_request.GET = {'somebadfield_max': str(start_time)}
+        fake_model = self.make_fake_model()
+        fake_model._meta.get_field_by_name('somebadfield')\
+                  .AndRaise(FieldDoesNotExist())
+        self.mox.ReplayAll()
+
+        self.assertRaises(dbapi.BadRequestException, dbapi._get_filter_args,
+                          fake_model, fake_request)
 
         self.mox.VerifyAll()