diff --git a/lib/committee/schema_validator/open_api_3.rb b/lib/committee/schema_validator/open_api_3.rb
index 0d8b7c27..13c23363 100644
--- a/lib/committee/schema_validator/open_api_3.rb
+++ b/lib/committee/schema_validator/open_api_3.rb
@@ -80,11 +80,13 @@ def request_unpack(request)
         request.env[validator_option.path_hash_key] = coerce_path_params
 
         query_param = unpacker.unpack_query_params(request)
+        param_matches_hash = request.env[validator_option.path_hash_key]
 
-        request.env[validator_option.params_key] = Committee::Utils.indifferent_hash
-        request.env[validator_option.params_key].merge!(Committee::Utils.deep_copy(query_param))
-        request.env[validator_option.params_key].merge!(Committee::Utils.deep_copy(request.env[validator_option.request_body_hash_key]))
-        request.env[validator_option.params_key].merge!(Committee::Utils.deep_copy(request.env[validator_option.path_hash_key]))
+        raise BadRequest, "Invalid JSON input. Require object with parameters as keys when path parameter exists." if !request_param.is_a?(Hash) && (query_param != {} || param_matches_hash != {})
+
+        request.env[validator_option.params_key] = Committee::Utils.deep_copy(request_param) || Committee::Utils.indifferent_hash
+        request.env[validator_option.params_key].merge!(Committee::Utils.deep_copy(query_param)) if query_param != {}
+        request.env[validator_option.params_key].merge!(Committee::Utils.deep_copy(param_matches_hash)) if param_matches_hash != {}
       end
 
       def copy_coerced_data_to_query_hash(request)
diff --git a/lib/committee/schema_validator/open_api_3/operation_wrapper.rb b/lib/committee/schema_validator/open_api_3/operation_wrapper.rb
index 00fce1bd..908ba0d0 100644
--- a/lib/committee/schema_validator/open_api_3/operation_wrapper.rb
+++ b/lib/committee/schema_validator/open_api_3/operation_wrapper.rb
@@ -115,7 +115,7 @@ def validate_post_request_params(params, headers, validator_option)
 
           # bad performance because when we coerce value, same check
           schema_validator_options = build_openapi_parser_post_option(validator_option)
-          request_operation.validate_request_parameter(params, headers, schema_validator_options)
+          request_operation.validate_request_parameter(params, headers, schema_validator_options) if params.is_a?(Hash)
           request_operation.validate_request_body(content_type, params, schema_validator_options)
         rescue => e
           raise Committee::InvalidRequest.new(e.message, original_error: e)