diff --git a/modules/checklists/load.php b/modules/checklists/load.php
index 791773e..b6c2eae 100644
--- a/modules/checklists/load.php
+++ b/modules/checklists/load.php
@@ -81,7 +81,7 @@ public function parse_lists_in_comment( $content, $comment = null ) {
 		return $this->parse_lists( $content );
 	}
 
-	function current_user_can_edit_checklist( $object_type, $object_ID ) {
+	public function current_user_can_edit_checklist( $object_type, $object_id ) {
 		// no logged out edits, evar
 		$current_user_id = get_current_user_id();
 		if ( 0 == $current_user_id ) {
@@ -89,10 +89,14 @@ function current_user_can_edit_checklist( $object_type, $object_ID ) {
 		}
 
 		// try default post and comment capabilities
-		if ( ( 'post' == $object_type ) && ( current_user_can( 'edit_post', $object_ID ) ) ) {
-			return true;
-		} else if ( ( 'comment' == $object_type ) && ( current_user_can( 'edit_comment', $object_ID ) ) ) {
+		if ( ( 'post' == $object_type ) && ( current_user_can( 'edit_post', $object_id ) ) ) {
 			return true;
+		} else if ( 'comment' == $object_type ) {
+			// Apply o2's comment rule: authors always edit their own comments
+			add_filter( 'map_meta_cap', array( 'o2_Write_API', 'restrict_comment_editing' ), 10, 4 );
+			$user_can_edit_comment = current_user_can( 'edit_comment', $object_id );
+			remove_filter( 'map_meta_cap', array( 'o2_Write_API', 'restrict_comment_editing' ), 10 );
+			return $user_can_edit_comment;
 		}
 
 		return false;
diff --git a/tests/phpunit/modules/test-checklists.php b/tests/phpunit/modules/test-checklists.php
new file mode 100644
index 0000000..644331d
--- /dev/null
+++ b/tests/phpunit/modules/test-checklists.php
@@ -0,0 +1,79 @@
+<?php
+
+class o2ChecklistsTest extends WP_UnitTestCase {
+
+	private $list_creator;
+
+	function setUp(): void {
+		parent::setUp();
+		$this->list_creator = new o2_List_Creator();
+	}
+
+	private function create_comment_on_another_authors_post( $commenter_id ) {
+		$post_owner_id = $this->factory->user->create( array( 'role' => 'author' ) );
+		$post_id = $this->factory->post->create( array( 'post_author' => $post_owner_id ) );
+
+		return $this->factory->comment->create( array(
+			'comment_post_ID' => $post_id,
+			'user_id' => $commenter_id,
+			'comment_content' => 'o my task',
+		) );
+	}
+
+	function test_author_can_edit_checklist_in_own_comment_on_another_authors_post() {
+		$author_id = $this->factory->user->create( array( 'role' => 'author' ) );
+		$comment_id = $this->create_comment_on_another_authors_post( $author_id );
+
+		wp_set_current_user( $author_id );
+
+		$this->assertTrue(
+			$this->list_creator->current_user_can_edit_checklist( 'comment', $comment_id ),
+			'An author should be able to edit checklists in their own comment'
+		);
+
+		$rendered = $this->list_creator->parse_lists_in_comment( 'o my task', get_comment( $comment_id ) );
+
+		$this->assertStringNotContainsString( 'disabled', $rendered, 'The checkbox should be enabled' );
+		$this->assertStringContainsString( 'o2-task-tools', $rendered, 'The task tools should be rendered' );
+	}
+
+	function test_author_cannot_edit_checklist_in_another_users_comment() {
+		$author_id = $this->factory->user->create( array( 'role' => 'author' ) );
+		$other_author_id = $this->factory->user->create( array( 'role' => 'author' ) );
+		$comment_id = $this->create_comment_on_another_authors_post( $other_author_id );
+
+		wp_set_current_user( $author_id );
+
+		$this->assertFalse(
+			$this->list_creator->current_user_can_edit_checklist( 'comment', $comment_id ),
+			'An author should not be able to edit checklists in another user\'s comment'
+		);
+
+		$rendered = $this->list_creator->parse_lists_in_comment( 'o my task', get_comment( $comment_id ) );
+
+		$this->assertStringContainsString( 'disabled', $rendered, 'The checkbox should be disabled' );
+		$this->assertStringNotContainsString( 'o2-task-tools', $rendered, 'The task tools should not be rendered' );
+	}
+
+	function test_editor_can_edit_checklist_in_another_users_comment() {
+		$editor_id = $this->factory->user->create( array( 'role' => 'editor' ) );
+		$author_id = $this->factory->user->create( array( 'role' => 'author' ) );
+		$comment_id = $this->create_comment_on_another_authors_post( $author_id );
+
+		wp_set_current_user( $editor_id );
+
+		$this->assertTrue(
+			$this->list_creator->current_user_can_edit_checklist( 'comment', $comment_id ),
+			'An editor should be able to edit checklists in any comment'
+		);
+	}
+
+	function test_logged_out_user_cannot_edit_checklist_in_comment() {
+		$author_id = $this->factory->user->create( array( 'role' => 'author' ) );
+		$comment_id = $this->create_comment_on_another_authors_post( $author_id );
+
+		wp_set_current_user( 0 );
+
+		$this->assertFalse( $this->list_creator->current_user_can_edit_checklist( 'comment', $comment_id ) );
+	}
+}