diff --git a/data-service/src/main/java/uk/gov/laa/ccms/data/controller/ProceedingController.java b/data-service/src/main/java/uk/gov/laa/ccms/data/controller/ProceedingController.java
index 528c7bf7..14b400f2 100644
--- a/data-service/src/main/java/uk/gov/laa/ccms/data/controller/ProceedingController.java
+++ b/data-service/src/main/java/uk/gov/laa/ccms/data/controller/ProceedingController.java
@@ -48,7 +48,8 @@ public ResponseEntity<ProceedingDetails> getProceedings(
       final Boolean larScopeFlag,
       final Pageable pageable) {
 
-    if (lead != null && lead) {
+
+    if (Boolean.TRUE.equals(lead)) {
       return ResponseEntity.ok(proceedingService.getLeadProceedings(
           categoryOfLaw,
           matterType,
diff --git a/data-service/src/main/java/uk/gov/laa/ccms/data/entity/LevelOfServiceId.java b/data-service/src/main/java/uk/gov/laa/ccms/data/entity/LevelOfServiceId.java
index 6cb01bff..47912b1f 100644
--- a/data-service/src/main/java/uk/gov/laa/ccms/data/entity/LevelOfServiceId.java
+++ b/data-service/src/main/java/uk/gov/laa/ccms/data/entity/LevelOfServiceId.java
@@ -33,6 +33,9 @@ public class LevelOfServiceId implements Serializable {
   @Column(name = "PROCEEDING_CODE")
   private String proceedingCode;
 
+  /**
+   * The level of service code.
+   */
   @Column(name = "LEVEL_OF_SERVICE_CODE")
   private String levelOfServiceCode;
 
diff --git a/data-service/src/main/java/uk/gov/laa/ccms/data/entity/MatterType.java b/data-service/src/main/java/uk/gov/laa/ccms/data/entity/MatterType.java
index a1ddf87b..f8b54095 100644
--- a/data-service/src/main/java/uk/gov/laa/ccms/data/entity/MatterType.java
+++ b/data-service/src/main/java/uk/gov/laa/ccms/data/entity/MatterType.java
@@ -22,13 +22,22 @@
 @JsonNaming(PropertyNamingStrategies.SnakeCaseStrategy.class)
 public class MatterType {
 
+  /**
+   * The unique identifier for the matter type.
+   */
   @Id
   @Column(name = "MATTER_TYPE")
   private String matterType;
 
+  /**
+   * The matter type's description.
+   */
   @Column(name = "DESCRIPTION")
   private String description;
 
+  /**
+   * The category of law code.
+   */
   @Column(name = "CATEGORY_OF_LAW_CODE")
   private String categoryOfLawCode;
 }
diff --git a/data-service/src/main/java/uk/gov/laa/ccms/data/entity/ProceedingClientInvolvementTypeId.java b/data-service/src/main/java/uk/gov/laa/ccms/data/entity/ProceedingClientInvolvementTypeId.java
index 0093b46f..b497637b 100644
--- a/data-service/src/main/java/uk/gov/laa/ccms/data/entity/ProceedingClientInvolvementTypeId.java
+++ b/data-service/src/main/java/uk/gov/laa/ccms/data/entity/ProceedingClientInvolvementTypeId.java
@@ -22,7 +22,7 @@ public class ProceedingClientInvolvementTypeId implements Serializable {
   private String proceedingCode;
 
   /**
-   * The stage end value.
+   * The client involvement type.
    */
   @Column(name = "CLIENT_INVOLVEMENT_TYPE")
   private String clientInvolvementType;
diff --git a/data-service/src/main/java/uk/gov/laa/ccms/data/repository/ProceedingRepository.java b/data-service/src/main/java/uk/gov/laa/ccms/data/repository/ProceedingRepository.java
index 47229747..d384dd04 100644
--- a/data-service/src/main/java/uk/gov/laa/ccms/data/repository/ProceedingRepository.java
+++ b/data-service/src/main/java/uk/gov/laa/ccms/data/repository/ProceedingRepository.java
@@ -42,9 +42,9 @@ public interface ProceedingRepository extends ReadOnlyRepository<Proceeding, Str
   Page<Proceeding> findAllLeadProceedings(
       @Param("categoryOfLaw") String categoryOfLaw,
       @Param("matterType") String matterType,
-      @Param("amendmentOnly") String amendmentOnly,
-      @Param("enabled") String enabled,
-      @Param("larScopeFlag") String larScopeFlag,
+      @Param("amendmentOnly") Character amendmentOnly,
+      @Param("enabled") Character enabled,
+      @Param("larScopeFlag") Character larScopeFlag,
       @Param("appOrCertType") String appOrCertType,
       Pageable pageable);
 
diff --git a/data-service/src/main/java/uk/gov/laa/ccms/data/service/ProceedingService.java b/data-service/src/main/java/uk/gov/laa/ccms/data/service/ProceedingService.java
index d7b9e489..1f476476 100644
--- a/data-service/src/main/java/uk/gov/laa/ccms/data/service/ProceedingService.java
+++ b/data-service/src/main/java/uk/gov/laa/ccms/data/service/ProceedingService.java
@@ -6,6 +6,7 @@
 import org.springframework.data.domain.Example;
 import org.springframework.data.domain.Pageable;
 import org.springframework.stereotype.Service;
+import uk.gov.laa.ccms.data.entity.BooleanConverter;
 import uk.gov.laa.ccms.data.entity.Proceeding;
 import uk.gov.laa.ccms.data.mapper.ProceedingMapper;
 import uk.gov.laa.ccms.data.model.ProceedingDetail;
@@ -31,6 +32,7 @@ public class ProceedingService extends AbstractEbsDataService {
 
   private final ProceedingMapper proceedingMapper;
 
+
   /**
    * Get Proceedings which match the provided category of law, matter type,
    * amendment only, and enabled values.
@@ -78,17 +80,15 @@ public ProceedingDetails getLeadProceedings(
       Boolean larScopeFlag,
       Pageable pageable) {
 
-    String amendmentOnlyString = (amendmentOnly != null) ? (amendmentOnly ? "Y" : "N") : null;
-    String enabledString = (enabled != null) ? (enabled ? "Y" : "N") : null;
-    String larScopeFlagString = (larScopeFlag != null) ? (larScopeFlag ? "Y" : "N") : null;
+    BooleanConverter booleanConverter = new BooleanConverter();
 
     return proceedingMapper.toProceedingDetails(
         proceedingRepository.findAllLeadProceedings(
             categoryOfLaw,
             matterType,
-            amendmentOnlyString,
-            enabledString,
-            larScopeFlagString,
+            booleanConverter.convertToDatabaseColumn(amendmentOnly),
+            booleanConverter.convertToDatabaseColumn(enabled),
+            booleanConverter.convertToDatabaseColumn(larScopeFlag),
             applicationType,
             pageable));
   }
diff --git a/data-service/src/test/java/uk/gov/laa/ccms/data/service/ProceedingServiceTest.java b/data-service/src/test/java/uk/gov/laa/ccms/data/service/ProceedingServiceTest.java
index 6b1df5e5..d0ddc45b 100644
--- a/data-service/src/test/java/uk/gov/laa/ccms/data/service/ProceedingServiceTest.java
+++ b/data-service/src/test/java/uk/gov/laa/ccms/data/service/ProceedingServiceTest.java
@@ -105,11 +105,11 @@ void getProceedings_returnsPageOfProceeding() {
     }, nullValues = "null")
     void getLeadProceedings_returnsPageOfLeadProceeding(
         Boolean amendmentOnly,
-        String expectedAmendmentOnlyString,
+        Character expectedAmendmentOnlyString,
         Boolean enabled,
-        String expectedEnabledString,
+        Character expectedEnabledString,
         Boolean larScope,
-        String expectedLarScopeString) {
+        Character expectedLarScopeString) {
         String categoryOfLaw = "CAT1";
         String matterType = "MAT1";
         String appOrCertType = "APP1";