Steps to reproduce the issue

In /administrator/components/com_menus/model/items.php, function:

protected function getListQuery()

    // Filter the items over the parent id if set.
    $parentId = $this->getState('filter.parent_id');

    if (!empty($parentId))
    {
        $query->where('p.id = ' . (int) $parentId);
    }

But p.id causes an SQL error (there is no table with p alias in the query build. Probably it should be:

    // Filter the items over the parent id if set.
    $parentId = $this->getState('filter.parent_id');

    if (!empty($parentId))
    {
        //$query->where('p.id = ' . (int) $parentId);
        $query->where('a.parent_id = ' . (int) $parentId);
    }

System information (as much as possible)

The issue was detected in Joomla 3.5.1