diff --git a/services/test/spam_svc_test.py b/services/test/spam_svc_test.py
new file mode 100644
index 0000000..3aeba13
--- /dev/null
+++ b/services/test/spam_svc_test.py
@@ -0,0 +1,433 @@
+# Copyright 2016 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file or at
+# https://developers.google.com/open-source/licenses/bsd
+
+"""Tests for the spam service."""
+from __future__ import print_function
+from __future__ import division
+from __future__ import absolute_import
+
+import mock
+import unittest
+
+import mox
+
+from google.appengine.ext import testbed
+
+import settings
+from framework import sql
+from framework import framework_constants
+from proto import user_pb2
+from proto import tracker_pb2
+from services import spam_svc
+from testing import fake
+from mock import Mock
+
+
+def assert_unreached():
+  raise Exception('This code should not have been called.')  # pragma: no cover
+
+
+class SpamServiceTest(unittest.TestCase):
+
+  def setUp(self):
+    self.testbed = testbed.Testbed()
+    self.testbed.activate()
+
+    self.mox = mox.Mox()
+    self.mock_report_tbl = self.mox.CreateMock(sql.SQLTableManager)
+    self.mock_verdict_tbl = self.mox.CreateMock(sql.SQLTableManager)
+    self.mock_issue_tbl = self.mox.CreateMock(sql.SQLTableManager)
+    self.cnxn = self.mox.CreateMock(sql.MonorailConnection)
+    self.issue_service = fake.IssueService()
+    self.spam_service = spam_svc.SpamService()
+    self.spam_service.report_tbl = self.mock_report_tbl
+    self.spam_service.verdict_tbl = self.mock_verdict_tbl
+    self.spam_service.issue_tbl = self.mock_issue_tbl
+
+    self.spam_service.report_tbl.Delete = Mock()
+    self.spam_service.verdict_tbl.Delete = Mock()
+
+  def tearDown(self):
+    self.testbed.deactivate()
+    self.mox.UnsetStubs()
+    self.mox.ResetAll()
+
+  def testLookupIssuesFlaggers(self):
+    self.mock_report_tbl.Select(
+        self.cnxn, cols=['issue_id', 'user_id', 'comment_id'],
+        issue_id=[234, 567, 890]).AndReturn([
+            [234, 111, None],
+            [234, 222, 1],
+            [567, 333, None]])
+    self.mox.ReplayAll()
+
+    reporters = (
+        self.spam_service.LookupIssuesFlaggers(self.cnxn, [234, 567, 890]))
+    self.mox.VerifyAll()
+    self.assertEqual({
+        234: ([111], {1: [222]}),
+        567: ([333], {}),
+    }, reporters)
+
+  def testLookupIssueFlaggers(self):
+    self.mock_report_tbl.Select(
+        self.cnxn, cols=['issue_id', 'user_id', 'comment_id'],
+        issue_id=[234]).AndReturn(
+            [[234, 111, None], [234, 222, 1]])
+    self.mox.ReplayAll()
+
+    issue_reporters, comment_reporters = (
+        self.spam_service.LookupIssueFlaggers(self.cnxn, 234))
+    self.mox.VerifyAll()
+    self.assertItemsEqual([111], issue_reporters)
+    self.assertEqual({1: [222]}, comment_reporters)
+
+  def testFlagIssues_overThresh(self):
+    issue = fake.MakeTestIssue(
+        project_id=789,
+        local_id=1,
+        reporter_id=111,
+        owner_id=456,
+        summary='sum',
+        status='Live',
+        issue_id=78901,
+        project_name='proj')
+    issue.assume_stale = False  # We will store this issue.
+
+    self.mock_report_tbl.InsertRows(self.cnxn,
+        ['issue_id', 'reported_user_id', 'user_id'],
+        [(78901, 111, 111)], ignore=True)
+
+    self.mock_report_tbl.Select(self.cnxn,
+        cols=['issue_id', 'COUNT(*)'], group_by=['issue_id'],
+        issue_id=[78901]).AndReturn([(78901, settings.spam_flag_thresh)])
+    self.mock_verdict_tbl.Select(
+        self.cnxn, cols=['issue_id', 'reason', 'MAX(created)'],
+        group_by=['issue_id'], issue_id=[78901], comment_id=None).AndReturn([])
+    self.mock_verdict_tbl.InsertRows(
+        self.cnxn, ['issue_id', 'is_spam', 'reason', 'project_id'],
+        [(78901, True, 'threshold', 789)], ignore=True)
+
+    self.mox.ReplayAll()
+    self.spam_service.FlagIssues(
+        self.cnxn, self.issue_service, [issue], 111, True)
+    self.mox.VerifyAll()
+    self.assertIn(issue, self.issue_service.updated_issues)
+
+    self.assertEqual(
+        1,
+        self.spam_service.issue_actions.get(
+            fields={
+                'type': 'flag',
+                'reporter_id': str(111),
+                'issue': 'proj:1'
+            }))
+
+  def testFlagIssues_underThresh(self):
+    issue = fake.MakeTestIssue(
+        project_id=789,
+        local_id=1,
+        reporter_id=111,
+        owner_id=456,
+        summary='sum',
+        status='Live',
+        issue_id=78901,
+        project_name='proj')
+
+    self.mock_report_tbl.InsertRows(self.cnxn,
+        ['issue_id', 'reported_user_id', 'user_id'],
+        [(78901, 111, 111)], ignore=True)
+
+    self.mock_report_tbl.Select(self.cnxn,
+        cols=['issue_id', 'COUNT(*)'], group_by=['issue_id'],
+        issue_id=[78901]).AndReturn([(78901, settings.spam_flag_thresh - 1)])
+
+    self.mock_verdict_tbl.Select(
+        self.cnxn, cols=['issue_id', 'reason', 'MAX(created)'],
+        group_by=['issue_id'], issue_id=[78901], comment_id=None).AndReturn([])
+
+    self.mox.ReplayAll()
+    self.spam_service.FlagIssues(
+        self.cnxn, self.issue_service, [issue], 111, True)
+    self.mox.VerifyAll()
+
+    self.assertNotIn(issue, self.issue_service.updated_issues)
+    self.assertIsNone(
+        self.spam_service.issue_actions.get(
+            fields={
+                'type': 'flag',
+                'reporter_id': str(111),
+                'issue': 'proj:1'
+            }))
+
+  def testUnflagIssue_overThresh(self):
+    issue = fake.MakeTestIssue(
+        project_id=789, local_id=1, reporter_id=111, owner_id=456,
+        summary='sum', status='Live', issue_id=78901, is_spam=True)
+    self.mock_report_tbl.Delete(self.cnxn, issue_id=[issue.issue_id],
+        comment_id=None, user_id=111)
+    self.mock_report_tbl.Select(self.cnxn,
+        cols=['issue_id', 'COUNT(*)'], group_by=['issue_id'],
+        issue_id=[78901]).AndReturn([(78901, settings.spam_flag_thresh)])
+
+    self.mock_verdict_tbl.Select(
+        self.cnxn, cols=['issue_id', 'reason', 'MAX(created)'],
+        group_by=['issue_id'], issue_id=[78901], comment_id=None).AndReturn([])
+
+    self.mox.ReplayAll()
+    self.spam_service.FlagIssues(
+        self.cnxn, self.issue_service, [issue], 111, False)
+    self.mox.VerifyAll()
+
+    self.assertNotIn(issue, self.issue_service.updated_issues)
+    self.assertEqual(True, issue.is_spam)
+
+  def testUnflagIssue_underThresh(self):
+    """A non-member un-flagging an issue as spam should not be able
+    to overturn the verdict to ham. This is different from previous
+    behavior. See https://crbug.com/monorail/2232 for details."""
+    issue = fake.MakeTestIssue(
+        project_id=789, local_id=1, reporter_id=111, owner_id=456,
+        summary='sum', status='Live', issue_id=78901, is_spam=True)
+    issue.assume_stale = False  # We will store this issue.
+    self.mock_report_tbl.Delete(self.cnxn, issue_id=[issue.issue_id],
+        comment_id=None, user_id=111)
+    self.mock_report_tbl.Select(self.cnxn,
+        cols=['issue_id', 'COUNT(*)'], group_by=['issue_id'],
+        issue_id=[78901]).AndReturn([(78901, settings.spam_flag_thresh - 1)])
+
+    self.mock_verdict_tbl.Select(
+        self.cnxn, cols=['issue_id', 'reason', 'MAX(created)'],
+        group_by=['issue_id'], issue_id=[78901], comment_id=None).AndReturn([])
+
+    self.mox.ReplayAll()
+    self.spam_service.FlagIssues(
+        self.cnxn, self.issue_service, [issue], 111, False)
+    self.mox.VerifyAll()
+
+    self.assertNotIn(issue, self.issue_service.updated_issues)
+    self.assertEqual(True, issue.is_spam)
+
+  def testUnflagIssue_underThreshNoManualOverride(self):
+    issue = fake.MakeTestIssue(
+        project_id=789, local_id=1, reporter_id=111, owner_id=456,
+        summary='sum', status='Live', issue_id=78901, is_spam=True)
+    self.mock_report_tbl.Delete(self.cnxn, issue_id=[issue.issue_id],
+        comment_id=None, user_id=111)
+    self.mock_report_tbl.Select(self.cnxn,
+        cols=['issue_id', 'COUNT(*)'], group_by=['issue_id'],
+        issue_id=[78901]).AndReturn([(78901, settings.spam_flag_thresh - 1)])
+
+    self.mock_verdict_tbl.Select(
+        self.cnxn, cols=['issue_id', 'reason', 'MAX(created)'],
+        group_by=['issue_id'], comment_id=None,
+        issue_id=[78901]).AndReturn([(78901, 'manual', '')])
+
+    self.mox.ReplayAll()
+    self.spam_service.FlagIssues(
+        self.cnxn, self.issue_service, [issue], 111, False)
+    self.mox.VerifyAll()
+
+    self.assertNotIn(issue, self.issue_service.updated_issues)
+    self.assertEqual(True, issue.is_spam)
+
+  def testGetIssueClassifierQueue_noVerdicts(self):
+    self.mock_verdict_tbl.Select(self.cnxn,
+        cols=['issue_id', 'is_spam', 'reason', 'classifier_confidence',
+              'created'],
+        where=[
+             ('project_id = %s', [789]),
+             ('classifier_confidence <= %s',
+                 [settings.classifier_moderation_thresh]),
+             ('overruled = %s', [False]),
+             ('issue_id IS NOT NULL', []),
+        ],
+        order_by=[
+             ('classifier_confidence ASC', []),
+             ('created ASC', [])
+        ],
+        group_by=['issue_id'],
+        offset=0,
+        limit=10,
+    ).AndReturn([])
+
+    self.mock_verdict_tbl.SelectValue(self.cnxn,
+        col='COUNT(*)',
+        where=[
+            ('project_id = %s', [789]),
+            ('classifier_confidence <= %s',
+                [settings.classifier_moderation_thresh]),
+            ('overruled = %s', [False]),
+            ('issue_id IS NOT NULL', []),
+        ]).AndReturn(0)
+
+    self.mox.ReplayAll()
+    res, count = self.spam_service.GetIssueClassifierQueue(
+        self.cnxn, self.issue_service, 789)
+    self.mox.VerifyAll()
+
+    self.assertEqual([], res)
+    self.assertEqual(0, count)
+
+  def testGetIssueClassifierQueue_someVerdicts(self):
+    self.mock_verdict_tbl.Select(self.cnxn,
+        cols=['issue_id', 'is_spam', 'reason', 'classifier_confidence',
+              'created'],
+        where=[
+             ('project_id = %s', [789]),
+             ('classifier_confidence <= %s',
+                 [settings.classifier_moderation_thresh]),
+             ('overruled = %s', [False]),
+             ('issue_id IS NOT NULL', []),
+        ],
+        order_by=[
+             ('classifier_confidence ASC', []),
+             ('created ASC', [])
+        ],
+        group_by=['issue_id'],
+        offset=0,
+        limit=10,
+    ).AndReturn([[78901, 0, "classifier", 0.9, "2015-12-10 11:06:24"]])
+
+    self.mock_verdict_tbl.SelectValue(self.cnxn,
+        col='COUNT(*)',
+        where=[
+            ('project_id = %s', [789]),
+            ('classifier_confidence <= %s',
+                [settings.classifier_moderation_thresh]),
+            ('overruled = %s', [False]),
+            ('issue_id IS NOT NULL', []),
+        ]).AndReturn(10)
+
+    self.mox.ReplayAll()
+    res, count  = self.spam_service.GetIssueClassifierQueue(
+        self.cnxn, self.issue_service, 789)
+    self.mox.VerifyAll()
+    self.assertEqual(1, len(res))
+    self.assertEqual(10, count)
+    self.assertEqual(78901, res[0].issue_id)
+    self.assertEqual(False, res[0].is_spam)
+    self.assertEqual("classifier", res[0].reason)
+    self.assertEqual(0.9, res[0].classifier_confidence)
+    self.assertEqual("2015-12-10 11:06:24", res[0].verdict_time)
+
+  def testIsExempt_RegularUser(self):
+    author = user_pb2.MakeUser(111, email='test@example.com')
+    self.assertFalse(self.spam_service._IsExempt(author, False))
+    author = user_pb2.MakeUser(111, email='test@chromium.org.example.com')
+    self.assertFalse(self.spam_service._IsExempt(author, False))
+
+  def testIsExempt_ProjectMember(self):
+    author = user_pb2.MakeUser(111, email='test@example.com')
+    self.assertTrue(self.spam_service._IsExempt(author, True))
+
+  def testIsExempt_AllowlistedDomain(self):
+    author = user_pb2.MakeUser(111, email='test@google.com')
+    self.assertTrue(self.spam_service._IsExempt(author, False))
+
+  def testClassifyIssue_spam(self):
+    issue = fake.MakeTestIssue(
+        project_id=789, local_id=1, reporter_id=111, owner_id=456,
+        summary='sum', status='Live', issue_id=78901, is_spam=True)
+    self.spam_service._predict = lambda body: 1.0
+
+    # Prevent missing service inits to fail the test.
+    self.spam_service.ml_engine = True
+
+    comment_pb = tracker_pb2.IssueComment()
+    comment_pb.content = "this is spam"
+    reporter = user_pb2.MakeUser(111, email='test@test.com')
+    res = self.spam_service.ClassifyIssue(issue, comment_pb, reporter, False)
+    self.assertEqual(1.0, res['confidence_is_spam'])
+
+    reporter.email = 'test@chromium.org.spam.com'
+    res = self.spam_service.ClassifyIssue(issue, comment_pb, reporter, False)
+    self.assertEqual(1.0, res['confidence_is_spam'])
+
+    reporter.email = 'test.google.com@test.com'
+    res = self.spam_service.ClassifyIssue(issue, comment_pb, reporter, False)
+    self.assertEqual(1.0, res['confidence_is_spam'])
+
+  def testClassifyIssue_Allowlisted(self):
+    issue = fake.MakeTestIssue(
+        project_id=789, local_id=1, reporter_id=111, owner_id=456,
+        summary='sum', status='Live', issue_id=78901, is_spam=True)
+    self.spam_service._predict = assert_unreached
+
+    # Prevent missing service inits to fail the test.
+    self.spam_service.ml_engine = True
+
+    comment_pb = tracker_pb2.IssueComment()
+    comment_pb.content = "this is spam"
+    reporter = user_pb2.MakeUser(111, email='test@google.com')
+    res = self.spam_service.ClassifyIssue(issue, comment_pb, reporter, False)
+    self.assertEqual(0.0, res['confidence_is_spam'])
+    reporter.email = 'test@chromium.org'
+    res = self.spam_service.ClassifyIssue(issue, comment_pb, reporter, False)
+    self.assertEqual(0.0, res['confidence_is_spam'])
+
+  def testClassifyComment_spam(self):
+    self.spam_service._predict = lambda body: 1.0
+
+    # Prevent missing service inits to fail the test.
+    self.spam_service.ml_engine = True
+
+    commenter = user_pb2.MakeUser(111, email='test@test.com')
+    res = self.spam_service.ClassifyComment('this is spam', commenter, False)
+    self.assertEqual(1.0, res['confidence_is_spam'])
+
+    commenter.email = 'test@chromium.org.spam.com'
+    res = self.spam_service.ClassifyComment('this is spam', commenter, False)
+    self.assertEqual(1.0, res['confidence_is_spam'])
+
+    commenter.email = 'test.google.com@test.com'
+    res = self.spam_service.ClassifyComment('this is spam', commenter, False)
+    self.assertEqual(1.0, res['confidence_is_spam'])
+
+  def testClassifyComment_Allowlisted(self):
+    self.spam_service._predict = assert_unreached
+
+    # Prevent missing service inits to fail the test.
+    self.spam_service.ml_engine = True
+
+    commenter = user_pb2.MakeUser(111, email='test@google.com')
+    res = self.spam_service.ClassifyComment('this is spam', commenter, False)
+    self.assertEqual(0.0, res['confidence_is_spam'])
+
+    commenter.email = 'test@chromium.org'
+    res = self.spam_service.ClassifyComment('this is spam', commenter, False)
+    self.assertEqual(0.0, res['confidence_is_spam'])
+
+  def test_ham_classification(self):
+    actual = self.spam_service.ham_classification()
+    self.assertEqual(actual['confidence_is_spam'], 0.0)
+    self.assertEqual(actual['failed_open'], False)
+
+  def testExpungeUsersInSpam(self):
+    user_ids = [3, 4, 5]
+    self.spam_service.ExpungeUsersInSpam(self.cnxn, user_ids=user_ids)
+
+    self.spam_service.report_tbl.Delete.assert_has_calls(
+        [
+            mock.call(self.cnxn, reported_user_id=user_ids, commit=False),
+            mock.call(self.cnxn, user_id=user_ids, commit=False)
+        ])
+    self.spam_service.verdict_tbl.Delete.assert_called_once_with(
+        self.cnxn, user_id=user_ids, commit=False)
+
+  def testLookupIssueVerdicts(self):
+    self.spam_service.verdict_tbl.Select = Mock(return_value=[
+      [5, 10], [4, 11], [6, 12],
+    ])
+    actual = self.spam_service.LookupIssueVerdicts(self.cnxn, [4, 5, 6])
+
+    self.spam_service.verdict_tbl.Select.assert_called_once_with(
+        self.cnxn, cols=['issue_id', 'reason', 'MAX(created)'],
+        issue_id=[4, 5, 6], comment_id=None, group_by=['issue_id'])
+    self.assertEqual(actual, {
+      5: 10,
+      4: 11,
+      6: 12,
+    })