Cookie Consent Integration with Google Consent Mode

Google Consent Storage Types are as follows:

Google Consent Mode can be implemented in basic or advanced modes.

Basic

When Consent Mode is implemented in the basic version, the Google tags are prevented from loading until a user interacts with the consent banner.

Advanced

When Consent Mode is implemented in the advanced version, Google tags and consent mode APIs load when a user lands on the website. The tags and APIs then do the following:

Advanced mode implementation can be used for behavioral modeling.

Step 1: Mapping the OneTrust Cookie Categories to Google Consent Types

Step 2: Defining Consent Storage Type Defaults

To adjust your tags' behavior relative to the users' preferences, consent defaults must be defined. There are two options available to choose from when setting the default Google Consent Storage types:

Option 1: Defining Consent Defaults Using OneTrust CMP-GCM Template

The OneTrust CMP Template is available in the Tag Manager Community Template Gallery.

The advantage of the CMP template is the consent defaults are already built in the template, so it is not required to explicitly set the defaults on the website. Using this template, you can associate your OneTrust purpose IDs with the Google Consent Mode storage types so that Google Consent Mode setting defaults and updates will occur based on user consent.

Option 2: Defining Consent Defaults Without Using OneTrust CMP-GCM Template

To adjust your tags' behavior relative to consent, use the gtag('consent') API:

gtag('consent', '<consent_command>', {<consent_type_settings>});

where <consent_command> is one of:

Order of scripts:

Example 1, without CMP template and GTM script:

<script> 
  // Define dataLayer and the gtag function. 
  window.dataLayer = window.dataLayer || []; 
  function gtag(){dataLayer.push(arguments);} 
  
  gtag('set' , 'developer_id.dYWJhMj', true);

  // Default ad_storage to 'denied'. 
  gtag('consent', 'default', { 
        ad_storage: "denied", 
        analytics_storage: "denied", 
        functionality_storage: "denied", 
        personalization_storage: "denied", 
        security_storage: "denied",  
        ad_user_data: “denied”,
        ad_personalization: “denied”, 
'wait_for_update': 500 

  }); 
</script>
 
<!-- Google Tag Manager --> 
<script>(function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start': 
new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0], 
j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src= 
'https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f); 
})(window,document,'script','dataLayer','GTM-XXXXXX');</script> 
<!-- End Google Tag Manager --> 
 
<!-- OneTrust Cookies Consent Notice start --> 
 
<script src="https://cdn.cookielaw.org/scripttemplates/otSDKStub.js"  type="text/javascript" charset="UTF-8" data-domain-script="XXXXXX" ></script> 
<script type="text/javascript"> 
function OptanonWrapper() { } 
</script> 
<!-- OneTrust Cookies Consent Notice end -->  

Example 2, without CMP template and gtag script:

 <script> 
// Define dataLayer and the gtag function. 
window.dataLayer = window.dataLayer || []; 
function gtag(){dataLayer.push(arguments);} 
// Default ad_storage to 'denied' as a placeholder 
// Determine actual values based on business requirements 
gtag('consent', 'default', { 
  'ad_storage': 'denied' 
}); 
</script> 
<!-- Google tag (gtag.js) --> 
<script async src="https://www.googletagmanager.com/gtag/js?id=TAG_ID"> 
</script> 
 
<!-- OneTrust Cookies Consent Notice start --> 
 
<script src="https://cdn.cookielaw.org/scripttemplates/otSDKStub.js"  type="text/javascript" charset="UTF-8" data-domain-script="XXXXXX" ></script> 
<script type="text/javascript"> 
function OptanonWrapper() { } 
</script> 
<!-- OneTrust Cookies Consent Notice end --> 

Region-Specific Behavior

If you are proceeding without the OneTrust CMP template:

To change the default behavior of your tags for users from certain regions, specify a region in your consent command. By providing a region value, you can fine-tune defaults based on your users' geographic locations. For example, to set ad_storage to denied for users from Spain and California, and to set ad_storage to granted for all other users:

gtag('consent', 'default', {
  ‘ad_storage': 'denied',
  'region': ['ES', 'US-CA']
});
gtag('consent', 'default', {
  'ad_storage': 'granted'
});

For more information, see Configuring Geolocation Rules.

The most specific takes precedence. If two default consent commands occur on the same page with values for a region and subregion, the command with a more specific region will take effect.

For example, if you have ad_storage set to granted for the region US and ad_storage set to denied for the region US-CA, a visitor from California will have the more specific US-CA setting take effect. For this example, that would mean a visitor from US-CA would have ad_storage set to denied.

Testing the functionality of Google Consent Mode is crucial for ensuring compliance with data privacy regulations and providing a better user experience. Testing this functionality ensures that user consent is properly collected and tracked.

Checking the datalayer

The datalayer console command can be used to see the "consent" event that is triggered when the user provides or revokes consent for data processing in Google Consent Mode.

After using the datalayer console command, it is possible to see all the events that are being triggered on the domain. Within this list the "consent" event can be seen, which shows the default settings for Google Consent Mode and also any updates to these settings due to user interaction.

Before user interaction:

After user interaction:

If Google Tag Manager is being used, this "consent" event can also be tracked using the tag assistant preview mode available.

Before user interaction:

After user interaction:

 

There may also be tags within the Tag Manager container that do not have built-in consent checks, so additional consent checks will need to be added if user consent is necessary.

Leverage the following instructions on how to add Additional Consent Checks to tags:

Google has provided additional information about Consent Mode in their documentation here. Refer to the Goggle Consent Mode overview for detailed information about tag behavior by consent type and consent state.

Please reach out to a Google support resource for any additional information.

Additionally, please see the OneTrust Cookies, Cookie Blocking via Google Tag Manager, and Google Consent Mode Implementation Webinar and Previously Recorded Cookie Consent Office Hours.