diff --git a/buildspec/linuxE2ETests.yml b/buildspec/linuxE2ETests.yml
index 9ba5c1be9cc..def6dfd1cd0 100644
--- a/buildspec/linuxE2ETests.yml
+++ b/buildspec/linuxE2ETests.yml
@@ -37,7 +37,7 @@ phases:
         commands:
             - export HOME=/home/codebuild-user
             # Ignore failure until throttling issues are fixed.
-            - xvfb-run npm run testE2E; PREVIOUS_TEST_EXIT_CODE=$? npm run mergeReports
+            - xvfb-run npm run testE2E; npm run mergeReports -- "$?"
             - VCS_COMMIT_ID="${CODEBUILD_RESOLVED_SOURCE_VERSION}"
             - CI_BUILD_URL=$(echo $CODEBUILD_BUILD_URL | sed 's/#/%23/g')
             - CI_BUILD_ID="${CODEBUILD_BUILD_ID}"
diff --git a/buildspec/linuxIntegrationTests.yml b/buildspec/linuxIntegrationTests.yml
index da6a2531620..dacab125b89 100644
--- a/buildspec/linuxIntegrationTests.yml
+++ b/buildspec/linuxIntegrationTests.yml
@@ -92,7 +92,7 @@ phases:
     build:
         commands:
             - export HOME=/home/codebuild-user
-            - xvfb-run npm run testInteg; PREVIOUS_TEST_EXIT_CODE=$? npm run mergeReports
+            - xvfb-run npm run testInteg; npm run mergeReports -- "$?"
             - VCS_COMMIT_ID="${CODEBUILD_RESOLVED_SOURCE_VERSION}"
             - CI_BUILD_URL=$(echo $CODEBUILD_BUILD_URL | sed 's/#/%23/g')
             - CI_BUILD_ID="${CODEBUILD_BUILD_ID}"
diff --git a/buildspec/linuxTests.yml b/buildspec/linuxTests.yml
index 70fd31274ca..20f5b6a01f7 100644
--- a/buildspec/linuxTests.yml
+++ b/buildspec/linuxTests.yml
@@ -41,7 +41,7 @@ phases:
                     # Ensure that "foo | run_and_report" fails correctly.
                     set -o pipefail
                     . buildspec/shared/common.sh
-                    2>&1 xvfb-run npm test --silent; PREVIOUS_TEST_EXIT_CODE=$? npm run mergeReports | run_and_report 2 \
+                    2>&1 xvfb-run npm test --silent; npm run mergeReports -- "$?" | run_and_report 2 \
                         'rejected promise not handled' \
                         'This typically indicates a bug. Read https://developer.mozilla.org/docs/Web/JavaScript/Guide/Using_promises#error_handling'
                 }
diff --git a/scripts/mergeReports.ts b/scripts/mergeReports.ts
index f2159290a1c..7059162048a 100644
--- a/scripts/mergeReports.ts
+++ b/scripts/mergeReports.ts
@@ -53,16 +53,19 @@ async function mergeReports() {
 
     fs.writeFileSync(path.join(reportsDir, 'report.xml'), xml)
 
-    /**
-     * Retrieves the exit code from the previous test run execution.
-     *
-     * This allows us to:
-     * 1. Merge and upload test reports regardless of the test execution status
-     * 2. Preserve the original test run exit code
-     * 3. Report the test status back to CI
-     */
-    const exitCode = parseInt(process.env.PREVIOUS_TEST_EXIT_CODE || '0', 10)
-    process.exit(exitCode)
+    const exitCodeArg = process.argv[2]
+    if (exitCodeArg) {
+        /**
+         * Retrieves the exit code from the previous test run execution.
+         *
+         * This allows us to:
+         * 1. Merge and upload test reports regardless of the test execution status
+         * 2. Preserve the original test run exit code
+         * 3. Report the test status back to CI
+         */
+        const exitCode = parseInt(exitCodeArg || '0', 10)
+        process.exit(exitCode)
+    }
 }
 
 mergeReports()