diff --git a/src/main/java/Plate.java b/src/main/java/Plate.java
index 19ff86f..8f071e2 100644
--- a/src/main/java/Plate.java
+++ b/src/main/java/Plate.java
@@ -221,7 +221,7 @@ public class Plate {
                         if (rand.nextDouble() <= readErrorProb) {
                             readError = true;
                             StringBuilder spurious = new StringBuilder(cell[sIndex]);
-                            if (rand.nextDouble() > errorCollisionProb) {
+                            if (!distinctMisreadCounts.containsKey(cell[sIndex]) || rand.nextDouble() > errorCollisionProb) {
                                 distinctMisreadCounts.merge(cell[sIndex], 1, (oldValue, newValue) -> oldValue + newValue);
                                 for (int j = 0; j < distinctMisreadCounts.get(cell[sIndex]); j++) {
                                     spurious.append("*");