diff --git a/cmd/rekor-server/app/root.go b/cmd/rekor-server/app/root.go
index cebc28d2a..daae2e5db 100644
--- a/cmd/rekor-server/app/root.go
+++ b/cmd/rekor-server/app/root.go
@@ -117,6 +117,8 @@ Memory and file-based signers should only be used for testing.`)
 	rootCmd.PersistentFlags().String("redis_server.password", "", "Redis server password")
 	rootCmd.PersistentFlags().Bool("redis_server.enable-tls", false, "Whether to enable TLS verification when connecting to Redis endpoint")
 	rootCmd.PersistentFlags().Bool("redis_server.insecure-skip-verify", false, "Whether to skip TLS verification when connecting to Redis endpoint, only applicable when 'redis_server.enable-tls' is set to 'true'")
+	rootCmd.PersistentFlags().String("tls-ca-cert", "", "Certificate file to use for secure connections with Trillian server")
+	rootCmd.PersistentFlags().Bool("trillian_log_server.tls", false, "Use system trust store for TLS")
 
 	rootCmd.PersistentFlags().Bool("enable_attestation_storage", false, "enables rich attestation storage")
 	rootCmd.PersistentFlags().String("attestation_storage_bucket", "", "url for attestation storage bucket")
diff --git a/docker-compose.yml b/docker-compose.yml
index 91e7ccff7..de953770d 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -75,7 +75,12 @@ services:
       "--http_endpoint=0.0.0.0:8091",
       "--force_master",
       "--alsologtostderr",
+      "--tls_cert_file=/etc/tls/tls.crt",
+      "--tls_key_file=/etc/tls/tls.key"
     ]
+    volumes:
+      - /tests/sharding-testdata/tls.crt:/etc/tls/tls.crt
+      - /tests/sharding-testdata/tls.key:/etc/tls/tls.key
     restart: always # retry while mysql is starting up
     ports:
       - "8092:8091"
@@ -102,11 +107,13 @@ services:
       "--enable_stable_checkpoint",
       "--search_index.storage_provider=mysql",
       "--search_index.mysql.dsn=test:zaphod@tcp(mysql:3306)/test",
+      "--tls_ca_cert=/etc/tls/ca.crt"
       # Uncomment this for production logging
       # "--log_type=prod",
       ]
     volumes:
     - "/var/run/attestations:/var/run/attestations:z"
+    - /tests/sharding-testdata/ca.crt:/etc/tls/ca.crt
     restart: always # keep the server running
     ports:
       - "3000:3000"
diff --git a/pkg/api/api.go b/pkg/api/api.go
index aba59b25e..63983030a 100644
--- a/pkg/api/api.go
+++ b/pkg/api/api.go
@@ -22,12 +22,15 @@ import (
 	"crypto/x509"
 	"encoding/hex"
 	"fmt"
+	"os"
+	"path/filepath"
 
 	"github.com/google/trillian"
 	"github.com/redis/go-redis/v9"
 	"github.com/spf13/viper"
 	"golang.org/x/exp/slices"
 	"google.golang.org/grpc"
+	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/credentials/insecure"
 
 	"github.com/sigstore/rekor/pkg/indexstorage"
@@ -47,7 +50,32 @@ import (
 
 func dial(rpcServer string) (*grpc.ClientConn, error) {
 	// Set up and test connection to rpc server
-	creds := insecure.NewCredentials()
+	var creds credentials.TransportCredentials
+	tlsCACertFile := viper.GetString("tls_ca_cert")
+	useSystemTrustStore := viper.GetBool("trillian_log_server.tls")
+
+	if useSystemTrustStore {
+		creds = credentials.NewTLS(&tls.Config{
+			ServerName: rpcServer,
+			MinVersion: tls.VersionTLS12,
+		})
+	} else if tlsCACertFile == "" {
+		creds = insecure.NewCredentials()
+	} else {
+		tlsCaCert, err := os.ReadFile(filepath.Clean(tlsCACertFile))
+		if err != nil {
+			log.Logger.Fatalf("Failed to load tls_ca_cert:", err)
+		}
+		certPool := x509.NewCertPool()
+		if !certPool.AppendCertsFromPEM(tlsCaCert) {
+			return nil, fmt.Errorf("failed to append CA certificate to pool")
+		}
+		creds = credentials.NewTLS(&tls.Config{
+			ServerName: rpcServer,
+			RootCAs:    certPool,
+			MinVersion: tls.VersionTLS12,
+		})
+	}
 	conn, err := grpc.NewClient(rpcServer, grpc.WithTransportCredentials(creds))
 	if err != nil {
 		log.Logger.Fatalf("Failed to connect to RPC server:", err)
diff --git a/tests/sharding-testdata/ca.crt b/tests/sharding-testdata/ca.crt
new file mode 100644
index 000000000..982656da4
--- /dev/null
+++ b/tests/sharding-testdata/ca.crt
@@ -0,0 +1,19 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----
diff --git a/tests/sharding-testdata/tls.crt b/tests/sharding-testdata/tls.crt
new file mode 100644
index 000000000..518c80d78
--- /dev/null
+++ b/tests/sharding-testdata/tls.crt
@@ -0,0 +1,19 @@
+-----BEGIN CERTIFICATE-----
+MIIC/jCCAeagAwIBAgIUXBONalvsgMSSss6Ac9F+Qiy0RoMwDQYJKoZIhvcNAQEL
+BQAwEDEOMAwGA1UEAwwFTXkgQ0EwHhcNMjQwNzAyMTU0MDQwWhcNMjUwNzAyMTU0
+MDQwWjAeMRwwGgYDVQQDDBN0cmlsbGlhbi1sb2ctc2VydmVyMIIBIjANBgkqhkiG
+9w0BAQEFAAOCAQ8AMIIBCgKCAQEAuSy6h6wZ4C8HEmeZMnqwYviJiTcjxXArZaPx
+ytxrvUOKviyA7oRhepOtSwpuUGh38+yrW6g9fv0c88DLktOwsNGSNZx9Gn8P0cLO
+PO1qzXI0zxNwzaTvywHEpUHIynrEILwy5orAcuP004P3Wsx4k2vhe5YdWZBdcw2V
+MFbJxOcHVXcrgENsFJkn6M6IuJ3yx+YClaRmYdp8C2jn3uHl4XQt+33kPPiWVj6l
+lhW2vkpTzvBLQKwAav6ZCckJGCzUI7deYcZGEkSS0KYfzhH7oODZaLFaKywUHM61
+uqZ5N6e/HiNNpQdf5tI1Zqf6Aoa5YQSBvY9oynbCYoMdgUwOnQIDAQABo0IwQDAd
+BgNVHQ4EFgQUKR3YSbyQ7sBy5ekiKbOsOKR07CUwHwYDVR0jBBgwFoAUl0DFoHwm
+Rk33P99PkGCfnCcrzfQwDQYJKoZIhvcNAQELBQADggEBAEx7hg6YEh9r76afDGg/
+Wm/7cru3jyHKrJOogIdvYqmyCXVTez4ZanHKAfjqv8V/WCeW+ZXqjQsKwMy4napx
+GGc1JxvLrF5dO0LS0jRT32HD/qAV14HNV7anN0YotbxSenAJlHG7H6uxfHvo1k/R
+rte2JKUF0ut3P0cLIdnWGW6fIpB2lnmXFnb6FBtxRZFxFzsV+TBLX+1L0xOrFuvq
+lI6Fu4xav5UwJs1ZMf3LhpGVLk5jmvUhnuWXwMYkcWqcCV9R0NKk49xyZ3uU2KYN
+crCHIepUbe/efDWBZMexNDqOKMtedoE5gWP4VjYV+AK4e160zig9sJw6q6KCPdie
+y3E=
+-----END CERTIFICATE-----
diff --git a/tests/sharding-testdata/tls.key b/tests/sharding-testdata/tls.key
new file mode 100644
index 000000000..10595c5db
--- /dev/null
+++ b/tests/sharding-testdata/tls.key
@@ -0,0 +1,28 @@
+-----BEGIN PRIVATE KEY-----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+-----END PRIVATE KEY-----