If the individual who signed the Affidavit of Liability for a Colorado driver under the age of 18 no longer wishes to be legally responsible for that driver, that person may withdraw his or her signature and the permit or license will be

If the consenting adult decides to withdraw his or her signature from the Affidavit of Liability for a Colorado driver under the age of 18, the driver's license or permit will be canceled. [Parent Consent for Minor Affidavit of Liability and Guardianship, The Driver License, Colorado Driver Handbook]