$http.get().error() does not call .then() callback

I am still trying to learn Jasmine and test an Angular service. Currently I am trying to test the .success and error calls off http.get.

Service Call

    this.get = function (param1, param2) {

        return $http.get('api/something/get/param1/param2')
            .success(function (data) {
                return data;
            })
            .error(function() {
                return "Please select param1 AND param2";
            });
    };

Jasmine Tests

    it('service makes unsuccessful API call', function() {
        var response = "This is the response";

        httpBackend.when('GET', "api/something/Get/0/0").respond(404);

        var data;

        service.get(0, 0).then(function(result) {
            data = result;
        });

        httpBackend.flush();

        expect(data).toEqual("Please select param1 AND param2");


    });

    it('service makes successful API call', function () {
        var response = "This is the response";
        httpBackend.when('GET', "api/something/Get/0/0").respond(response);
        var data;

        service.get(0, 0).then(function(result) {
            data = result.data;
        });

        httpBackend.flush();

        expect(data).toEqual(response);


    });

In the first test (Error) the data = result.data line in then() is never called. On the expect(data).toEqual(), data is undefined. When I step through everything I see where the service is called and the error message is populated in result.data.

In the second test (Success), I see the same thing but the data is set when the then function is called.

Why is my then function not called on .error()?