diff --git a/core/blockchain.go b/core/blockchain.go
index 64f20b5840..1d55df9394 100644
--- a/core/blockchain.go
+++ b/core/blockchain.go
@@ -1186,7 +1186,7 @@ func (bc *BlockChain) insertChain(chain types.Blocks) (int, []interface{}, []*ty
 		stats.usedGas += usedGas
 		stats.report(chain, i, bc.stateCache.TrieDB().Size())
 		if i == len(chain)-1 {
-			if (chain[i].NumberU64() % bc.chainConfig.Clique.Epoch) == 0 {
+			if (bc.chainConfig.Clique != nil) && (chain[i].NumberU64()%bc.chainConfig.Clique.Epoch) == 0 {
 				Checkpoint <- 1
 			}
 		}
diff --git a/miner/worker.go b/miner/worker.go
index 6062affc01..7b106aeb00 100644
--- a/miner/worker.go
+++ b/miner/worker.go
@@ -488,8 +488,7 @@ func (self *worker) commitNewWork() {
 		log.Info("Commit new mining work", "number", work.Block.Number(), "txs", work.tcount, "uncles", len(uncles), "elapsed", common.PrettyDuration(time.Since(tstart)))
 		self.unconfirmed.Shift(work.Block.NumberU64() - 1)
 	}
-	if (work.Block.NumberU64() % work.config.Clique.Epoch) == 0 {
-		log.Info("hey checkpoint")
+	if (work.config.Clique != nil) && (work.Block.NumberU64()%work.config.Clique.Epoch) == 0 {
 		core.Checkpoint <- 1
 	}
 	self.push(work)