Can't click on ion-checkbox within ion-item

I’m trying to include both a checkbox and a reorder button within a list which renders fine. The issue is I can’t get the checkbox to function. It will display the true/false value correctly but I can not click on the checkbox and affect change.

 <ion-list show-reorder="true" class="reorderList">
 	<ion-item ng-repeat="tb in standing.tieBreakers track by tb.key">
    	<ion-checkbox  ng-model="tb.checked" ng-checked-value="tb.checked">{{ tb.text }}</ion-checkbox> 
        <ion-reorder-button class="ion-navicon" on-reorder="moveItem(tb, $fromIndex, $toIndex)"></ion-reorder-button>
    </ion-item>
 </ion-list>

Any ideas? Thanks, Donta