diff --git a/monitor/att.c b/monitor/att.c
index eb73934..e0164f3 100644
--- a/monitor/att.c
+++ b/monitor/att.c
@@ -2583,7 +2583,7 @@ static void media_state_notify(const struct l2cap_frame *frame)
 	print_media_state(frame);
 }
 
-struct media_cp_opcode {
+static const struct media_cp_opcode {
 	uint8_t opcode;
 	const char *opcode_str;
 } media_cp_opcode_table[] = {
@@ -2741,7 +2741,7 @@ static void content_control_id_read(const struct l2cap_frame *frame)
 
 static const struct pa_sync_state_decoder {
 	uint8_t code;
-	char *value;
+	const char *value;
 } pa_sync_state_decoders[] = {
 	{ 0x00, "Not synchronized to PA" },
 	{ 0x01, "SyncInfo Request" },
@@ -2752,7 +2752,7 @@ static const struct pa_sync_state_decoder {
 
 static const struct cp_pa_sync_state_decoder {
 	uint8_t code;
-	char *value;
+	const char *value;
 } cp_pa_sync_state_decoders[] = {
 	{ 0x00, "Do not synchronize to PA" },
 	{ 0x01, "Synchronize to PA - PAST available" },
@@ -2761,7 +2761,7 @@ static const struct cp_pa_sync_state_decoder {
 
 static const struct big_enc_decoder {
 	uint8_t code;
-	char *value;
+	const char *value;
 } big_enc_decoders[] = {
 	{ 0x00, "Not encrypted" },
 	{ 0x01, "Broadcast_Code required" },
diff --git a/monitor/avctp.c b/monitor/avctp.c
index fb26282..c59e93b 100644
--- a/monitor/avctp.c
+++ b/monitor/avctp.c
@@ -1802,7 +1802,7 @@ response:
 }
 
 
-static struct {
+static const struct {
 	const char *str;
 	bool reserved;
 } features_table[] = {
diff --git a/monitor/intel.c b/monitor/intel.c
index 0191987..1b24142 100644
--- a/monitor/intel.c
+++ b/monitor/intel.c
@@ -1798,7 +1798,7 @@ static const struct vendor_evt vendor_prefix_evt_table[] = {
 	{ }
 };
 
-const uint8_t intel_vendor_prefix[] = {0x87, 0x80};
+static const uint8_t intel_vendor_prefix[] = {0x87, 0x80};
 #define INTEL_VENDOR_PREFIX_SIZE sizeof(intel_vendor_prefix)
 
 /*
diff --git a/monitor/l2cap.c b/monitor/l2cap.c
index 8f3d8e6..dff183b 100644
--- a/monitor/l2cap.c
+++ b/monitor/l2cap.c
@@ -718,7 +718,7 @@ static void print_config_result(uint16_t result)
 	print_field("Result: %s (0x%4.4x)", str, le16_to_cpu(result));
 }
 
-static struct {
+static const struct {
 	uint8_t type;
 	uint8_t len;
 	const char *str;
diff --git a/monitor/rfcomm.c b/monitor/rfcomm.c
index 02300a8..a855152 100644
--- a/monitor/rfcomm.c
+++ b/monitor/rfcomm.c
@@ -32,7 +32,7 @@
 #include "sdp.h"
 #include "rfcomm.h"
 
-static char *cr_str[] = {
+static const char *cr_str[] = {
 	"RSP",
 	"CMD"
 };
diff --git a/monitor/sdp.c b/monitor/sdp.c
index daf9a9d..2c69dc8 100644
--- a/monitor/sdp.c
+++ b/monitor/sdp.c
@@ -167,7 +167,7 @@ static struct {
 	{ }
 };
 
-static struct {
+static const struct {
 	uint8_t index;
 	uint8_t bits;
 	uint8_t size;
@@ -322,7 +322,7 @@ static uint32_t get_bytes(const uint8_t *data, uint32_t size)
 	return 0;
 }
 
-static struct {
+static const struct {
 	uint16_t id;
 	const char *str;
 } attribute_table[] = {