This is a way to bind Bootstrap's accordion behavior directly in the view

gistfile1.html

<script>
ko.bindingHandlers.collapseAccordion = {
	init: function(element, valueAccessor, allBindingsAccessor, viewModel) {
		if($(element).hasClass("collapse")){
			$(element).removeClass("collapse").attr().addClass("in");
		} else {
			$(element).removeClass("in").addClass("collapse").attr("style","height:0px");
		}
	}
}
</script>

<div data-bind="collapseAccordion: conditionalStatement" class="accordion-body">
  ...
</div>