Uncheckable checkbox
HTML
<div class='test'>
<input type="checkbox" class='check' name="vehicle" value="Bike">I have a bike<br>
<input type="checkbox" class='check' name="vehicle" value="Car">I have a car
</div>
JavaScript
$('.test input[type="checkbox"]').change(function(e) {
e.preventDefault();
$('.check').prop('checked', true);
});