How object is authenticate through 'declarative_authorization'

I am using declarative_authorization in my app. I am bit confused how declarative_authorization is authenticate the object for the checking the authorization.

For example:

My authorization rule file is like:

role :Teacher do
  has_permission_on :results, :to => [:new, :create]
  has_permission_on :results, :to => [:show, :edit, :index, :update, :destroy] do
    if_attribute :user  => is {user}
  end
end

class MonitorsController < ApplicationController    
  def result
     @result = Result.find_by_user_id(params[user_id])
  end
end

I am displaying the result to teachers only.

In my view:

<% edit_permission = (permitted_to? :show, @results) %>
<% if edit_permission %>
  // display results
<% end %>

Problem: Issue is with the @results instance. It always returning false for @results object.

Query: Do we need to use filter_resource_access for authenticating the object. Because in my case I am manually fetching the result object instead of filter_resource_access.