HTML Select multiple without ctrl key

jquery.selectMultiple.js

/**
 * DWTFYW License
 * Author: Tony Brix, http://tonybrix.info
 * 
 * Set all multiple select elements to allow selecting multiple without using the ctrl key
 * 
 */
(function($){
	$.fn.selectMultiple = function(){
		return this.mousedown(function(e){
			e.preventDefault();
			//save scrollTop to prevent scrolling on selection change.
			//see: http://stackoverflow.com/questions/24543862/selecting-multiple-from-an-html-select-element-without-using-ctrl-key/
			var scroll = this.scrollTop;
			e.target.selected = !e.target.selected;
			this.scrollTop = scroll;
			$(this).focus();
		}).mousemove(function(e){e.preventDefault()});
	};
})(jQuery);
$("select[multiple]").selectMultiple();

Tried it and didn't work :(