Many employers have a policy of only giving job title and dates of employment, to prevent any possible lawsuit. However, if you say it with sufficient disgust

Many employers have a policy of only giving job title and dates of employment, to prevent any possible lawsuit. However, if you say it with sufficient disgust in your voice, it'll be obvious that you're giving a negative reference. Even if what you are saying is true, that still doesn't mean it can't lead to a lawsuit.