How to access Server side exception object in JS

I have a situation where i need to throw UserDefined Exception(setting Some message) from server side controller and need to show same message in the UI(angularJS $http call)

here is some sample code snippets

//In Server

@RequestMapping(value = "get-tax", method = RequestMethod.GET)
    public @ResponseBody Map<String,Object> getEligibleTaxes()throws GrnException{
        throw new GrnException("Catch Me if you can.....in UI");
    }

//In UI

var taxesResponse = GRNCommonService.getEligibleTaxes();
    taxesResponse.success(function(data, status, headers, config) {
        //console.log("Taxes :"+angular.toJson(data));
        if(data.status){
            GRNMasterInfo.setEligibleTaxes(data.responseData);
        }else{
            alert("Failed to Get Taxes Information!...Because :"+data.message);
        }
    });
    taxesResponse.error(function(data, status, headers, config) {
        console.log("Data :"+data);
        console.log("Status :"+status);
        console.log("Header :"+headers);
        console.log("Config :"+angular.toJson(config));
        alert("Failed to Get Taxes Information!");
    });