diff --git a/app/models/email_message.rb b/app/models/email_message.rb
index 5fdc1021..e2411e1c 100644
--- a/app/models/email_message.rb
+++ b/app/models/email_message.rb
@@ -31,6 +31,8 @@ class EmailMessage < ApplicationRecord
 
   attribute :uuid, :string, default: -> { SecureRandom.uuid }
 
+  normalizes :body, with: ->(value) { value.to_s }, apply_to_nil: true
+
   before_validation :set_sha1, on: :create
 
   def normalized_body
diff --git a/lib/params/submission_create_validator.rb b/lib/params/submission_create_validator.rb
index 523dd092..c33ed88a 100644
--- a/lib/params/submission_create_validator.rb
+++ b/lib/params/submission_create_validator.rb
@@ -29,8 +29,6 @@ module Params
       in_path(params, :message) do |message_params|
         type(message_params, :subject, String)
         type(message_params, :body, String)
-
-        required(message_params, :body)
       end
     end
 
@@ -53,8 +51,6 @@ module Params
       in_path(params, :message, skip_blank: true) do |message_params|
         type(message_params, :subject, String)
         type(message_params, :body, String)
-
-        required(message_params, :body)
       end
 
       value_in(params, :order, %w[preserved random], allow_nil: true)
@@ -119,8 +115,6 @@ module Params
       in_path(params, :message) do |message_params|
         type(message_params, :subject, String)
         type(message_params, :body, String)
-
-        required(message_params, :body)
       end
 
       value_in(params, :order, %w[preserved random], allow_nil: true)
diff --git a/lib/submitters.rb b/lib/submitters.rb
index 71041a3d..6a562390 100644
--- a/lib/submitters.rb
+++ b/lib/submitters.rb
@@ -143,7 +143,7 @@ module Submitters
   def normalize_preferences(account, user, params)
     preferences = {}
 
-    message_params = params['message'].presence || params.slice('subject', 'body').presence
+    message_params = (params['message'].presence || params.slice('subject', 'body')).compact_blank
 
     if message_params.present?
       email_message = EmailMessages.find_or_create_for_account_user(account, user,
diff --git a/spec/requests/submissions_spec.rb b/spec/requests/submissions_spec.rb
index 3adf6092..6dacc802 100644
--- a/spec/requests/submissions_spec.rb
+++ b/spec/requests/submissions_spec.rb
@@ -197,7 +197,7 @@ describe 'Submission API' do
       expect(response.parsed_body).to eq({ 'error' => 'Defined more signing parties than in template' })
     end
 
-    it 'returns an error if the message has no body value' do
+    it 'creates a submission when the message has only a subject' do
       post '/api/submissions', headers: { 'x-auth-token': author.access_token.token }, params: {
         template_id: templates[0].id,
         send_email: true,
@@ -209,8 +209,13 @@ describe 'Submission API' do
         }
       }.to_json
 
-      expect(response).to have_http_status(:unprocessable_content)
-      expect(response.parsed_body).to eq({ 'error' => 'body is required in `message`.' })
+      expect(response).to have_http_status(:ok)
+
+      submission = Submission.last
+      email_message = EmailMessage.last
+
+      expect(submission.submitters.first.preferences['email_message_uuid']).to eq(email_message.uuid)
+      expect(email_message).to have_attributes(subject: 'Custom Email Subject', body: '')
     end
   end