diff --git a/main.tf b/main.tf
index 604d3c0..8ccfe57 100644
--- a/main.tf
+++ b/main.tf
@@ -42,8 +42,8 @@
  */
 
 locals {
-  aws_acmpca_certificate_authority_arn = "${coalesce(element(concat(aws_acmpca_certificate_authority.msk_kafka_with_ca.*.arn, list("")), 0), element(concat(aws_acmpca_certificate_authority.msk_kafka_ca_with_config.*.arn, list("")), 0))}"
-  msk_cluster_arn                      = "${coalesce(element(concat(aws_msk_cluster.msk_kafka.*.arn, list("")), 0), element(concat(aws_msk_cluster.msk_kafka_with_config.*.arn, list("")), 0))}"
+  aws_acmpca_certificate_authority_arn = var.certificateauthority == "true" ? coalesce(element(concat(aws_acmpca_certificate_authority.msk_kafka_with_ca.*.arn, list("")), 0), element(concat(aws_acmpca_certificate_authority.msk_kafka_ca_with_config.*.arn, list("")), 0)) : ""
+  msk_cluster_arn                      = coalesce(element(concat(aws_msk_cluster.msk_kafka.*.arn, list("")), 0), element(concat(aws_msk_cluster.msk_kafka_with_config.*.arn, list("")), 0))
 }
 
 data "aws_caller_identity" "current" {}