diff --git a/main.tf b/main.tf
index 6a8e88c..76d5d80 100644
--- a/main.tf
+++ b/main.tf
@@ -51,9 +51,9 @@ module "lambda" {
       DYNAMODB_TIME_TO_LIVE = var.dynamodb_time_to_live
       DYNAMODB_TABLE_NAME   = try(module.cloudtrail_to_slack_dynamodb_table[0].dynamodb_table_id, "")
 
+      USE_DEFAULT_RULES = var.use_default_rules
+      PUSH_ACCESS_DENIED_CLOUDWATCH_METRICS = var.push_access_denied_cloudwatch_metrics
     },
-    var.use_default_rules ? { USE_DEFAULT_RULES = "True" } : {},
-    var.push_access_denied_cloudwatch_metrics ? { PUSH_ACCESS_DENIED_CLOUDWATCH_METRICS = "True" } : {}
   )
 
   memory_size = var.lambda_memory_size
diff --git a/src/config.py b/src/config.py
index 1292e79..ae2cdcb 100644
--- a/src/config.py
+++ b/src/config.py
@@ -61,12 +61,12 @@ def __init__(self): # noqa: ANN101 ANN204
         self.rules_separator: str = os.environ.get("RULES_SEPARATOR", ",")
         self.user_rules: List[str] = self.parse_rules_from_string(os.environ.get("RULES"), self.rules_separator) # noqa: E501
         self.ignore_rules: List[str] = self.parse_rules_from_string(os.environ.get("IGNORE_RULES"), self.rules_separator) # noqa: E501
-        self.use_default_rules: bool = os.environ.get("USE_DEFAULT_RULES", True) # type: ignore # noqa: PGH003
+        self.use_default_rules: bool = self.get_bool_from_env_var("USE_DEFAULT_RULES")
         self.events_to_track: str | None = os.environ.get("EVENTS_TO_TRACK")
 
         self.dynamodb_table_name: str | None = os.environ.get("DYNAMODB_TABLE_NAME")
         self.dynamodb_time_to_live: int = int(os.environ.get("DYNAMODB_TIME_TO_LIVE", 900))
-        self.push_access_denied_cloudwatch_metrics: bool = os.environ.get("PUSH_ACCESS_DENIED_CLOUDWATCH_METRICS") # type: ignore # noqa: PGH003, E501
+        self.push_access_denied_cloudwatch_metrics: bool = self.get_bool_from_env_var("PUSH_ACCESS_DENIED_CLOUDWATCH_METRICS")
 
         self.rules = []
         if self.use_default_rules:
@@ -87,6 +87,10 @@ def parse_rules_from_string(rules_as_string: str | None, rules_separator: str) -
         # make sure there are no empty strings in the list
         return [x for x in rules_as_list if x]
 
+    @staticmethod
+    def get_bool_from_env_var(env_var_name: str) -> bool:
+        return os.environ.get(env_var_name, "").lower() in ["true", "1"]
+
 
 
 class JsonFormatter(logging.Formatter):