diff --git a/internal/service/api/handlers/verify.go b/internal/service/api/handlers/verify.go
index 2b896c2..2913a00 100644
--- a/internal/service/api/handlers/verify.go
+++ b/internal/service/api/handlers/verify.go
@@ -10,6 +10,7 @@ import (
 	providers "github.com/rarimo/kyc-service/internal/service/core/identity_providers"
 	"github.com/rarimo/kyc-service/internal/service/core/identity_providers/civic"
 	gcpsp "github.com/rarimo/kyc-service/internal/service/core/identity_providers/gitcoin_passport"
+	"github.com/rarimo/kyc-service/internal/service/core/identity_providers/kleros"
 	"github.com/rarimo/kyc-service/internal/service/core/identity_providers/worldcoin"
 
 	"github.com/rarimo/kyc-service/internal/data"
@@ -69,5 +70,6 @@ func isUnauthorizedError(err error) bool {
 		errors.Is(err, providers.ErrNonceNotFound) ||
 		errors.Is(err, worldcoin.ErrNotLikelyHuman) ||
 		errors.Is(err, gcpsp.ErrScoreIsTooLow) ||
-		errors.Is(err, civic.ErrInvalidGatewayToken)
+		errors.Is(err, civic.ErrInvalidGatewayToken) ||
+		errors.Is(err, kleros.ErrIsNotRegistered)
 }
diff --git a/internal/service/core/identity_providers/kleros/main.go b/internal/service/core/identity_providers/kleros/main.go
index c5911ca..7667e77 100644
--- a/internal/service/core/identity_providers/kleros/main.go
+++ b/internal/service/core/identity_providers/kleros/main.go
@@ -2,22 +2,22 @@ package kleros
 
 import (
 	"encoding/json"
-	cryptoPkg "github.com/ethereum/go-ethereum/crypto"
-	"github.com/rarimo/kyc-service/internal/config"
-	"github.com/rarimo/kyc-service/internal/crypto"
-	"github.com/rarimo/kyc-service/internal/service/core/identity_providers/kleros/contracts"
 	"time"
 
 	"github.com/ethereum/go-ethereum/common"
+	cryptoPkg "github.com/ethereum/go-ethereum/crypto"
 	"gitlab.com/distributed_lab/logan/v3"
 	"gitlab.com/distributed_lab/logan/v3/errors"
 
+	"github.com/rarimo/kyc-service/internal/config"
+	"github.com/rarimo/kyc-service/internal/crypto"
 	"github.com/rarimo/kyc-service/internal/data"
 	providers "github.com/rarimo/kyc-service/internal/service/core/identity_providers"
+	"github.com/rarimo/kyc-service/internal/service/core/identity_providers/kleros/contracts"
 	"github.com/rarimo/kyc-service/internal/service/core/issuer"
 )
 
-type Kleros struct { // TODO?
+type Kleros struct {
 	logger                  *logan.Entry
 	masterQ                 data.MasterQ
 	proofOfHumanityContract *contracts.ProofOfHumanity
@@ -113,7 +113,7 @@ func (k *Kleros) checkIfIsRegistered(userAddress common.Address) error {
 		return errors.Wrap(err, "failed to call isRegistered contract method")
 	}
 	if !isRegistered {
-		return errors.New("user is not registered")
+		return ErrIsNotRegistered
 	}
 	return nil
 }
diff --git a/internal/service/core/identity_providers/kleros/models.go b/internal/service/core/identity_providers/kleros/models.go
index af9dd04..7a00972 100644
--- a/internal/service/core/identity_providers/kleros/models.go
+++ b/internal/service/core/identity_providers/kleros/models.go
@@ -3,10 +3,14 @@ package kleros
 import (
 	"github.com/ethereum/go-ethereum/common"
 	validation "github.com/go-ozzo/ozzo-validation/v4"
+	"github.com/pkg/errors"
+
 	"github.com/rarimo/kyc-service/internal/service/api/requests"
 	"github.com/rarimo/kyc-service/resources"
 )
 
+var ErrIsNotRegistered = errors.New("user is not registered")
+
 type (
 	// VerificationData is a data that is required by Kleros to verify a user
 	VerificationData resources.KlerosData