diff --git a/index.js b/index.js
index f81fffb..cd4787f 100644
--- a/index.js
+++ b/index.js
@@ -46,12 +46,12 @@ internals.Router.prototype.route = function(event, context) {
   var self = this;
   return new Promise((resolve, reject) => {
     if (context == null) {
-      let error = processError(Boom.badImplementation('context is required'));
+      let error = this._processError(Boom.badImplementation('context is required'));
       return reject(error);
     }
     var result = Joi.validate(event, eventSchema);
     if (result.error) {
-      let error = processError(result.error);
+      let error = this._processError(result.error);
       return reject(error);
     }
 
@@ -63,32 +63,33 @@ internals.Router.prototype.route = function(event, context) {
             return resolve(response);
           })
           .catch((error) => {
-            var errorStatus = (error.isBoom) ? error.output.payload : error;
-            return reject(errorStatus);
+            let newError = this._processError(error);
+            return reject(newError);
           });
       } else {
-        let error = processError(Boom.notImplemented(event.context['http-method'] + ' handler for path [' + event.context['resource-path'] + '] not registered'));
+        let error = this._processError(Boom.notImplemented(event.context['http-method'] + ' handler for path [' + event.context['resource-path'] + '] not registered'));
         return reject(error);
       }
     } else {
-      let error = processError(Boom.badImplementation('Request context, method, and path are required'));
+      let error = this._processError(Boom.badImplementation('Request context, method, and path are required'));
       return reject(error);
     }
   });
 };
 
-function processError(error) {
+internals.Router.prototype._processError = function(error) {
+  var transformed = error;
   if (error.isJoi) {
-    error = validationError(error);
+    transformed = this._validationError(error);
   }
 
-  if (error.isBoom) {
-    error = error.output.payload;
+  if (transformed.isBoom) {
+    transformed = transformed.output.payload;
   }
-  return error;
+  return transformed;
 }
 
-function validationError(error) {
+internals.Router.prototype._validationError = function(error) {
   var errorValue;
   errorValue = Boom.badRequest('Invalid request input: ' + error.message);
   if (error.details) {
diff --git a/test/test-router.js b/test/test-router.js
index e2d3d68..08f5ea8 100644
--- a/test/test-router.js
+++ b/test/test-router.js
@@ -4,6 +4,7 @@
 
 var Lambda = require('../index');
 var Boom = require('boom');
+var Joi = require('joi');
 
 var router;
 
@@ -198,7 +199,7 @@ describe('Router:@unit', () => {
 
     });
 
-    it('should fail when request causes handler to reject', (done) => {
+    it('should fail when request causes handler reject', (done) => {
       var route = {
         path: '/hello',
         method: 'GET',
@@ -229,7 +230,42 @@ describe('Router:@unit', () => {
 
     });
 
-    it('should fail with a Boom payload when request causes handler to reject', (done) => {
+    it('should transform error when handler rejects with a ValidationError', (done) => {
+      var route = {
+        path: '/hello',
+        method: 'GET',
+        handler: (event, context) => {
+          return new Promise((resolve, reject) => {
+            var schema = Joi.string();
+            var result = Joi.validate(1, schema);
+            expect(result.error).to.exist;
+            return reject(result.error);
+          });
+        }
+      };
+      var event = {
+        context: {
+          'resource-path': '/hello',
+          'http-method': 'GET'
+        }
+      };
+      router.register(route);
+      router.route(event, context)
+        .then((response) => {
+          expect(response).to.not.exist;
+          context.done(null, response);
+          done();
+        })
+        .catch((error) => {
+          expect(error).to.exist;
+          expect(error.statusCode).to.equal(400);
+          context.done(error, null);
+          done();
+        });
+
+    });
+
+    it('should fail with a badImplementation error when request causes handler to reject', (done) => {
       var route = {
         path: '/hello',
         method: 'GET',
@@ -259,7 +295,7 @@ describe('Router:@unit', () => {
           done();
         });
     });
-    it('should fail with a Boom payload when request has invalid properties', (done) => {
+    it('should fail with a badImplementation error when request has invalid properties', (done) => {
       var route = {
         path: '/hello',
         method: 'GET',