```coffeescript
class window.FactRelation extends Backbone.Model

  defaults:
    evidence_type: 'FactRelation'

  setOpinion: (type) ->
    $.ajax
      url: @url() + "/opinion/" + type
      success: (data) =>
        mp_track "Evidence: opinionate",
          type: type
          evidence_id: @id

        @set data

      type: "post"

  removeOpinion: ->
    $.ajax
      url: "#{@url()}/opinion"
      type: "delete"
      success: (data) =>
        @set data

  getFact: ->
    return @_fact if @_fact?

    @_fact = new Fact(@get('from_fact'))
    @on 'change', =>
      @_fact.set @get('from_fact')
    @_fact

  believe: -> @setOpinion "believes"
  disbelieve: -> @setOpinion "disbelieves"

  isBelieving: -> @get('current_user_opinion') == 'believes'
  isDisBelieving: -> @get('current_user_opinion') == 'disbelieves'

  creator: -> new User(@get('created_by'))

  can_destroy: -> @get 'can_destroy?'

  urlRoot: -> @collection.factRelationsUrl()

  validate: (attributes) ->
    unless attributes.evidence_id? or /^.*\S.*$/.test(attributes.displaystring)
      'Should have either an evidence_id or a displaystring'
```

Add current_opinion getter to FactRelation
user
```coffeescript
class window.FactRelation extends Backbone.Model

  defaults:
    evidence_type: 'FactRelation'

  setOpinion: (type) ->
    $.ajax
      url: @url() + "/opinion/" + type
      success: (data) =>
        mp_track "Evidence: opinionate",
          type: type
          evidence_id: @id

        @set data

      type: "post"

  removeOpinion: ->
    $.ajax
      url: "#{@url()}/opinion"
      type: "delete"
      success: (data) =>
        @set data

  getFact: ->
    return @_fact if @_fact?

    @_fact = new Fact(@get('from_fact'))
    @on 'change', =>
      @_fact.set @get('from_fact')
    @_fact

  believe: -> @setOpinion "believes"
  disbelieve: -> @setOpinion "disbelieves"

  isBelieving: -> @get('current_user_opinion') == 'believes'
  isDisBelieving: -> @get('current_user_opinion') == 'disbelieves'

  current_opinion: -> @get('current_user_opinion')

  creator: -> new User(@get('created_by'))

  can_destroy: -> @get 'can_destroy?'

  urlRoot: -> @collection.factRelationsUrl()

  validate: (attributes) ->
    unless attributes.evidence_id? or /^.*\S.*$/.test(attributes.displaystring)
      'Should have either an evidence_id or a displaystring'
```
assistant