diff --git a/lib/buildkite/test_collector/session.rb b/lib/buildkite/test_collector/session.rb
index 16404f0..8c37623 100644
--- a/lib/buildkite/test_collector/session.rb
+++ b/lib/buildkite/test_collector/session.rb
@@ -7,6 +7,10 @@ class Session
     MAX_RECONNECTION_ATTEMPTS = ENV.fetch("BUILDKITE_ANALYTICS_RECONNECTION_ATTEMPTS") { 3 }.to_i
     WAIT_BETWEEN_RECONNECTIONS = ENV.fetch("BUILDKITE_ANALYTICS_RECONNECTION_WAIT") { 5 }.to_i
 
+    # We keep a private reference so that mocking libraries won't break JSON
+    JSON_PARSE = JSON.method(:parse)
+    private_constant :JSON_PARSE
+
     class RejectedSubscription < StandardError; end
     class InitialConnectionFailure < StandardError; end
 
@@ -120,7 +124,7 @@ def close(examples_count)
     end
 
     def handle(_connection, data)
-      data = JSON.parse(data)
+      data = JSON_PARSE.call(data)
       case data["type"]
       when "ping"
         # In absence of other message, the server sends us a ping every 3 seconds
diff --git a/spec/test_collector/session_spec.rb b/spec/test_collector/session_spec.rb
index 7ee1dbf..dfbbe07 100644
--- a/spec/test_collector/session_spec.rb
+++ b/spec/test_collector/session_spec.rb
@@ -53,6 +53,12 @@
       session.handle(socket_double, {"type"=> "message", "identifier"=> "fake_channel", "message" => {"confirm"=> ["./spec/analytics/session_spec.rb[1:1]"]}}.to_json)
       expect(session.unconfirmed_idents_count).to be 0
     end
+
+    it "is immune to JSON.parse being mocked" do
+      allow(JSON).to receive(:parse).and_raise(JSON::ParserError)
+
+      session.handle(socket_double, {"type"=> "message", "identifier"=> "fake_channel", "message" => {"confirm"=> ["./spec/analytics/session_spec.rb[1:1]"]}}.to_json)
+    end
   end
 
   describe "#close" do