diff --git a/lib/utils/warn-on-deprecation.js b/lib/utils/warn-on-deprecation.js
new file mode 100644
index 00000000..caca86fb
--- /dev/null
+++ b/lib/utils/warn-on-deprecation.js
@@ -0,0 +1,16 @@
+/* eslint-disable no-console */
+
+/**
+ * Outputs a deprecation message.
+ * Supports silencing the messages based on the environmental variable.
+ * @param {string} message
+ */
+module.exports = function warnOnDeprecation(message) {
+  const shouldOutputMessage =
+    typeof process === 'undefined' ||
+    !process.env.SUPPRESS_DEPRECATION_WARNINGS;
+
+  if (shouldOutputMessage) {
+    console.warn(`DEPRECATED: ${message}`);
+  }
+};
diff --git a/lib/validators/json-schema-legacy.js b/lib/validators/json-schema-legacy.js
index d54dc9ca..bef19fc5 100644
--- a/lib/validators/json-schema-legacy.js
+++ b/lib/validators/json-schema-legacy.js
@@ -5,6 +5,7 @@ const jsonPointer = require('json-pointer');
 const { JsonSchemaValidator, META_SCHEMA } = require('./json-schema-next');
 const { ValidationErrors } = require('./validation-errors');
 const toGavelResult = require('../utils/to-gavel-result');
+const warnOnDeprecation = require('../utils/warn-on-deprecation');
 
 /**
  * Returns a proper article for a given string.
@@ -76,6 +77,10 @@ class JsonSchemaLegacy extends JsonSchemaValidator {
 
     switch (this.jsonSchemaVersion) {
       case 'draftV3':
+        warnOnDeprecation(
+          'JSON Schema Draft V3 is deprecated. Please use a newer version of JSON Schema (Draft V4-7).'
+        );
+
         return this.validateUsingAmanda(parsedData);
       case 'draftV4':
         return this.validateUsingTV4(parsedData);