diff --git a/app/models/legislation/process.rb b/app/models/legislation/process.rb
index a57f53564..f59ddf377 100644
--- a/app/models/legislation/process.rb
+++ b/app/models/legislation/process.rb
@@ -54,7 +54,35 @@ class Legislation::Process < ApplicationRecord
     validates :"#{phase_name}_end_date", presence: true, if: enabled_attribute
   end
 
-  validate :valid_date_ranges
+  validates :end_date,
+            comparison: {
+              greater_than_or_equal_to: :start_date,
+              message: :invalid_date_range
+            },
+            allow_blank: true,
+            if: -> { start_date }
+  validates :debate_end_date,
+            comparison: {
+              greater_than_or_equal_to: :debate_start_date,
+              message: :invalid_date_range
+            },
+            allow_blank: true,
+            if: -> { debate_start_date }
+  validates :draft_end_date,
+            comparison: {
+              greater_than_or_equal_to: :draft_start_date,
+              message: :invalid_date_range
+            },
+            allow_blank: true,
+            if: -> { draft_start_date }
+  validates :allegations_end_date,
+            comparison: {
+              greater_than_or_equal_to: :allegations_start_date,
+              message: :invalid_date_range
+            },
+            allow_blank: true,
+            if: -> { allegations_start_date }
+
   validates :background_color, format: { allow_blank: true, with: ->(*) { CSS_HEX_COLOR }}
   validates :font_color, format: { allow_blank: true, with: ->(*) { CSS_HEX_COLOR }}
 
@@ -140,22 +168,4 @@ class Legislation::Process < ApplicationRecord
   def self.search(terms)
     pg_search(terms)
   end
-
-  private
-
-    def valid_date_ranges
-      if end_date && start_date && end_date < start_date
-        errors.add(:end_date, :invalid_date_range)
-      end
-      if debate_end_date && debate_start_date && debate_end_date < debate_start_date
-        errors.add(:debate_end_date, :invalid_date_range)
-      end
-      if draft_end_date && draft_start_date && draft_end_date < draft_start_date
-        errors.add(:draft_end_date, :invalid_date_range)
-      end
-      if allegations_end_date && allegations_start_date &&
-         allegations_end_date < allegations_start_date
-        errors.add(:allegations_end_date, :invalid_date_range)
-      end
-    end
 end
diff --git a/app/models/poll.rb b/app/models/poll.rb
index 8f5da2b3e..5fda6f884 100644
--- a/app/models/poll.rb
+++ b/app/models/poll.rb
@@ -34,9 +34,22 @@ class Poll < ApplicationRecord
 
   validates_translation :name, presence: true
   validate :date_range
-  validate :start_date_is_not_past_date, on: :create
+  validates :starts_at,
+            comparison: {
+              greater_than_or_equal_to: ->(*) { Time.current },
+              message: ->(*) { I18n.t("errors.messages.past_date") }
+            },
+            allow_blank: true,
+            on: :create
+  validates :ends_at,
+            comparison: {
+              greater_than_or_equal_to: ->(*) { Time.current },
+              message: ->(*) { I18n.t("errors.messages.past_date") }
+            },
+            on: :update,
+            if: -> { will_save_change_to_ends_at? }
+
   validate :start_date_change, on: :update
-  validate :end_date_is_not_past_date, on: :update
   validate :end_date_change, on: :update
   validate :only_one_active, unless: :public?
 
@@ -168,12 +181,6 @@ class Poll < ApplicationRecord
     end
   end
 
-  def start_date_is_not_past_date
-    if starts_at.present? && starts_at < Time.current
-      errors.add(:starts_at, I18n.t("errors.messages.past_date"))
-    end
-  end
-
   def start_date_change
     if will_save_change_to_starts_at?
       if starts_at_in_database < Time.current
@@ -184,12 +191,6 @@ class Poll < ApplicationRecord
     end
   end
 
-  def end_date_is_not_past_date
-    if will_save_change_to_ends_at? && ends_at < Time.current
-      errors.add(:ends_at, I18n.t("errors.messages.past_date"))
-    end
-  end
-
   def end_date_change
     if will_save_change_to_ends_at? && ends_at_in_database < Time.current
       errors.add(:ends_at, I18n.t("errors.messages.cannot_change_date.poll_ended"))