Display a list of all roles defined on the system. If a role name is provided as an argument, then all of the permissions of that role will be listed. If a permission name is provided as an option, then all of the roles that have been granted that permission will be listed.
drush role-list
role : The role to list. Optional; if specified, lists all permissions assigned to that role. If no role is specified, lists all of the roles available on the system.
--filter : Limits the list of roles to only those that have been assigned the specified permission. Optional; may not be specified if a role argument is provided.
Display a list of roles that have the administer nodes permission assigned.
drush role-list --filter='administer nodes'
Display all of the permissions assigned to the anon user role.
drush role-list 'anonymous user'