diff --git a/merlin-server/src/main/java/gov/nasa/jpl/aerie/merlin/server/http/MerlinBindings.java b/merlin-server/src/main/java/gov/nasa/jpl/aerie/merlin/server/http/MerlinBindings.java
index ac2ee5c9e3..9b4575e8ce 100644
--- a/merlin-server/src/main/java/gov/nasa/jpl/aerie/merlin/server/http/MerlinBindings.java
+++ b/merlin-server/src/main/java/gov/nasa/jpl/aerie/merlin/server/http/MerlinBindings.java
@@ -6,6 +6,7 @@
 import gov.nasa.jpl.aerie.merlin.protocol.types.InstantiationException;
 import gov.nasa.jpl.aerie.merlin.server.exceptions.NoSuchPlanDatasetException;
 import gov.nasa.jpl.aerie.merlin.server.exceptions.NoSuchPlanException;
+import gov.nasa.jpl.aerie.merlin.server.exceptions.SimulationDatasetMismatchException;
 import gov.nasa.jpl.aerie.merlin.server.services.ConstraintAction;
 import gov.nasa.jpl.aerie.merlin.server.models.HasuraAction;
 import gov.nasa.jpl.aerie.merlin.server.models.PlanId;
@@ -250,6 +251,8 @@ private void getConstraintViolations(final Context ctx) {
       ctx.status(404).result(ExceptionSerializers.serializeNoSuchPlanException(ex).toString());
     } catch (final InputMismatchException ex) {
       ctx.status(404).result(ResponseSerializers.serializeInputMismatchException(ex).toString());
+    } catch (SimulationDatasetMismatchException ex) {
+      ctx.status(404).result(ResponseSerializers.serializeSimulationDatasetMismatchException(ex).toString());
     } catch (final PermissionsServiceException ex) {
       ctx.status(503).result(ExceptionSerializers.serializePermissionsServiceException(ex).toString());
     } catch (final Unauthorized ex) {
diff --git a/merlin-server/src/main/java/gov/nasa/jpl/aerie/merlin/server/remotes/postgres/PostgresConstraintRepository.java b/merlin-server/src/main/java/gov/nasa/jpl/aerie/merlin/server/remotes/postgres/PostgresConstraintRepository.java
index ef5d823dc2..13a29000d5 100644
--- a/merlin-server/src/main/java/gov/nasa/jpl/aerie/merlin/server/remotes/postgres/PostgresConstraintRepository.java
+++ b/merlin-server/src/main/java/gov/nasa/jpl/aerie/merlin/server/remotes/postgres/PostgresConstraintRepository.java
@@ -35,8 +35,9 @@ public void insertConstraintRuns(
 
   @Override
   public Map<Long, ConstraintRunRecord> getValidConstraintRuns(List<Long> constraintIds, SimulationDatasetId simulationDatasetId) {
-    try (final var connection = this.dataSource.getConnection()) {
-      final var constraintRuns = new GetValidConstraintRunsAction(connection, constraintIds, simulationDatasetId).get();
+    try (final var connection = this.dataSource.getConnection();
+         final var validConstraintRunAction = new GetValidConstraintRunsAction(connection, constraintIds, simulationDatasetId)) {
+      final var constraintRuns = validConstraintRunAction.get();
       final var validConstraintRuns = new HashMap<Long, ConstraintRunRecord>();
 
       for (final var constraintRun : constraintRuns) {
diff --git a/merlin-server/src/main/java/gov/nasa/jpl/aerie/merlin/server/services/ConstraintAction.java b/merlin-server/src/main/java/gov/nasa/jpl/aerie/merlin/server/services/ConstraintAction.java
index fbe49780d3..3cdeb271cd 100644
--- a/merlin-server/src/main/java/gov/nasa/jpl/aerie/merlin/server/services/ConstraintAction.java
+++ b/merlin-server/src/main/java/gov/nasa/jpl/aerie/merlin/server/services/ConstraintAction.java
@@ -9,6 +9,7 @@
 import gov.nasa.jpl.aerie.constraints.time.Interval;
 import gov.nasa.jpl.aerie.constraints.tree.Expression;
 import gov.nasa.jpl.aerie.merlin.protocol.types.Duration;
+import gov.nasa.jpl.aerie.merlin.server.exceptions.SimulationDatasetMismatchException;
 import gov.nasa.jpl.aerie.merlin.server.models.SimulationDatasetId;
 import gov.nasa.jpl.aerie.merlin.server.models.SimulationResultsHandle;
 import gov.nasa.jpl.aerie.merlin.server.exceptions.NoSuchPlanException;
@@ -23,7 +24,6 @@
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
-import java.util.Map;
 import java.util.Optional;
 
 public class ConstraintAction {
@@ -48,10 +48,16 @@ public ConstraintAction(
   }
 
   public List<ConstraintResult> getViolations(final PlanId planId, final Optional<SimulationDatasetId> simulationDatasetId)
-  throws NoSuchPlanException, MissionModelService.NoSuchMissionModelException
-  {
+      throws NoSuchPlanException, MissionModelService.NoSuchMissionModelException, SimulationDatasetMismatchException {
     final var plan = this.planService.getPlanForValidation(planId);
-    final var revisionData = this.planService.getPlanRevisionData(planId);
+    final Optional<SimulationResultsHandle> resultsHandle$;
+    if(simulationDatasetId.isPresent()){
+      resultsHandle$ = this.simulationService.get(planId, simulationDatasetId.get());
+    } else {
+      resultsHandle$ = this.simulationService.get(planId);
+    }
+
+
     final var constraintCode = new HashMap<Long, Constraint>();
 
     try {
@@ -61,10 +67,9 @@ public List<ConstraintResult> getViolations(final PlanId planId, final Optional<
       throw new RuntimeException("Assumption falsified -- mission model for existing plan does not exist");
     }
 
-    final var resultsHandle$ = this.simulationService.get(planId, revisionData);
-    final var simDatasetId = simulationDatasetId.orElseGet(() -> resultsHandle$
+    final var simDatasetId = resultsHandle$
         .map(SimulationResultsHandle::getSimulationDatasetId)
-        .orElseThrow(() -> new InputMismatchException("no simulation datasets found for plan id " + planId.id())));
+        .orElseThrow(() -> new InputMismatchException("no simulation datasets found for plan id " + planId.id()));
     final var violations = new HashMap<Long, ConstraintResult>();
 
     final var validConstraintRuns = this.constraintService.getValidConstraintRuns(constraintCode.values().stream().toList(), simDatasetId);