Can a previous employer say you were a bad employee?

I believe so, especially if it is true. If they lie and say you were a bad employee, they would be taking a risk, however, I guess they could if they wanted to.

AnswerMost WON'T, for fear they'll be sued. Many companies have a policy of only verifying dates of employment and salary. Some will also divulge if you're considered "rehirable." Some small business owners just don't care, and will say whatever they think. If you did something really bad (stole $1,000 or assualted a co-worker) the previous employer may use tone of voice or an indirect way to convey the info that you're not recommended. If you're in doubt, put someone else down as a reference.

Typically to avoid lawsuits claiming slander or defamation of character most employers are restricted to only verifying the date that you were hired and the date that you left the company,and yes or no if they would re-hire you in the future...

However if you were say arrested (and CONVICTED)in a court of law for committing a crime against the company,then that employer could devulge that information because your criminal conviction is public knowledge and it is not considered slander or defamation to release public knowledge....