Untitled

What is the best way to bypass devise authorization for a specific record marked public
GET /events/:id

skip_before_filter :authenticate_user!, :only => :show, :if => lambda {
    if params[:id]
      @event = Event.find(params[:id])
      @event and @event.public?
    else
      false
    end
  }

can :read, Event do |e|
  some_other_authorization_boolean || e.public?
end