diff --git a/ssl_exporter_test.go b/ssl_exporter_test.go
index a5a2fb5..86f3ea9 100644
--- a/ssl_exporter_test.go
+++ b/ssl_exporter_test.go
@@ -1,7 +1,11 @@
 package main
 
 import (
+	"crypto/tls"
+	"crypto/x509"
+	"encoding/pem"
 	"fmt"
+	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
 	"regexp"
@@ -10,29 +14,52 @@ import (
 )
 
 func TestProbeHandler(t *testing.T) {
+	certContent, err := ioutil.ReadFile("test/badssl.com-client.pem")
+	if err != nil {
+		t.Fatalf("Can't read test client certificate from disk")
+	}
+
+	keyContent, err := ioutil.ReadFile("test/badssl.com-client-key.pem")
+	if err != nil {
+		t.Fatalf("Can't read test client certificate key from disk")
+	}
+
+	keyBlock, _ := pem.Decode(keyContent)
+
+	keyBlockDecrypted, err := x509.DecryptPEMBlock(keyBlock, []byte("badssl.com"))
+	if err != nil {
+		t.Fatalf("Issue decrypting test client key")
+	}
+
+	emptyRootCAs := x509.NewCertPool()
+
+	certificate, err := tls.X509KeyPair(certContent, keyBlockDecrypted)
 
 	// Test the behaviour of various target URIs
 	//    'ok' denotes whether we expect a succesful https connection
-	//    'insecure' denotes whether we ignore invalid certs
 	cases := []struct {
-		uri      string
-		ok       bool
-		insecure bool
+		uri       string
+		ok        bool
+		tlsConfig *tls.Config
 	}{
 		// Test against an assumed valid, reachable and functioning HTTPS address
-		{uri: "https://google.com", ok: true, insecure: false},
+		{uri: "https://google.com", ok: true, tlsConfig: &tls.Config{}},
 		// Test against a HTTP address
-		{uri: "http://google.com", ok: false, insecure: false},
+		{uri: "http://google.com", ok: false, tlsConfig: &tls.Config{}},
 		// Test against an expired certificate when we're rejecting invalid certs
-		{uri: "https://expired.badssl.com", ok: false, insecure: false},
+		{uri: "https://expired.badssl.com", ok: false, tlsConfig: &tls.Config{}},
 		// Test against an expired certificate when we're accepting invalid certs
-		{uri: "https://expired.badssl.com", ok: true, insecure: true},
+		{uri: "https://expired.badssl.com", ok: true, tlsConfig: &tls.Config{InsecureSkipVerify: true}},
 		// Test against a target with no protocol
-		{uri: "google.com", ok: false, insecure: false},
+		{uri: "google.com", ok: false, tlsConfig: &tls.Config{}},
 		// Test against a string with spaces
-		{uri: "with spaces", ok: false, insecure: false},
+		{uri: "with spaces", ok: false, tlsConfig: &tls.Config{}},
 		// Test against nothing
-		{uri: "", ok: false, insecure: false},
+		{uri: "", ok: false, tlsConfig: &tls.Config{}},
+		// Test with client authentication
+		{uri: "https://client.badssl.com", ok: true, tlsConfig: &tls.Config{Certificates: []tls.Certificate{certificate}}},
+		// Test with an empty root CA bundle
+		{uri: "https://google.com", ok: false, tlsConfig: &tls.Config{RootCAs: emptyRootCAs}},
 	}
 
 	fmt.Println("Note: The error logs in these tests are expected. One of the important tests is that we return the expected body, even in the face of errors.")
@@ -47,7 +74,7 @@ func TestProbeHandler(t *testing.T) {
 
 		rr := httptest.NewRecorder()
 		handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			probeHandler(w, r, test.insecure)
+			probeHandler(w, r, test.tlsConfig)
 		})
 
 		handler.ServeHTTP(rr, req)
diff --git a/test/badssl.com-client-key.pem b/test/badssl.com-client-key.pem
new file mode 100644
index 0000000..39c929d
--- /dev/null
+++ b/test/badssl.com-client-key.pem
@@ -0,0 +1,30 @@
+-----BEGIN RSA PRIVATE KEY-----
+Proc-Type: 4,ENCRYPTED
+DEK-Info: DES-EDE3-CBC,8906E5B87ECB8682
+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+-----END RSA PRIVATE KEY-----
diff --git a/test/badssl.com-client.pem b/test/badssl.com-client.pem
new file mode 100644
index 0000000..90fb671
--- /dev/null
+++ b/test/badssl.com-client.pem
@@ -0,0 +1,27 @@
+-----BEGIN CERTIFICATE-----
+MIIEnTCCAoWgAwIBAgIJAPC7KMFjfslXMA0GCSqGSIb3DQEBCwUAMH4xCzAJBgNV
+BAYTAlVTMRMwEQYDVQQIDApDYWxpZm9ybmlhMRYwFAYDVQQHDA1TYW4gRnJhbmNp
+c2NvMQ8wDQYDVQQKDAZCYWRTU0wxMTAvBgNVBAMMKEJhZFNTTCBDbGllbnQgUm9v
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+A1UEBwwNU2FuIEZyYW5jaXNjbzEPMA0GA1UECgwGQmFkU1NMMSIwIAYDVQQDDBlC
+YWRTU0wgQ2xpZW50IENlcnRpZmljYXRlMIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8A
+MIIBCgKCAQEAxzdfEeseTs/rukjly6MSLHM+Rh0enA3Ai4Mj2sdl31x3SbPoen08
+utVhjPmlxIUdkiMG4+ffe7N+JtDLG75CaxZp9CxytX7kywooRBJsRnQhmQPca8MR
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+MJXciJZWr3QXvFdBH7m0zwpKgQ1wm6j3yeyuRphq2lEtU3OQl55A3tXtvqyMXsxk
+xMCCNQdmKQt0WYmMS3Xj/AfAY2sjCWziDflvW5mGCUjSYdZ+r3JIIF4m/FNCIO1d
+Ioacp9qb0qL9duFlVHtFiPgoKrEdJaNVUL7NG9ppF8pR
+-----END CERTIFICATE-----