Does an Employer have to provide a reference?
An employer is under no legal obligation to give a former employee a job reference at all. Therefore, if your employer refuses to give a reference, they are well within their rights to not provide you with one.
However, if they do provide a reference, they are under a legal duty to not give a false reference. This is why many employers only provide factual references stating the name, job title and dates of employment. They do this in order to avoid being held liable for any inaccurate more detailed job references.
Can you sue someone for giving you a bad reference?
If your employer provides an inaccurate or negligent job reference, you can sue them to recover damages. This claim would be brought in the County Court, NOT the Employment Tribunal.
In order for the claim to be successful, you must have suffered a financial loss. An example of this would be if you failed to get a new job because of the bad reference and subsequently lost the income that your new job would have provided.