Selenium, JAVA - error in @After

My @After function is:

  public void tearDown() throws Exception {
    driver.quit();
    String verificationErrorString = verificationErrors.toString();
    if (!"".equals(verificationErrorString)) {
      fail(verificationErrorString);
    }
  }

and when I run the test I get an error:

java.lang.AddesrtionError: java.langAssertionErrorjava.lang.AssertionError

at tear.Down, line:

      fail(verificationErrorString);

How to fix this one?