Insurance is a heated debate, and yes, you are in part covered by your employer--however, as a previous poster mentioned, you are only covered for the time that you were employed...so if a suit is filed after you leave, and you are involved, you will no longer be covered. Something to think about--and yes, you will still be implicated, regardless of whether or not you have insurance...money is money, and they don't care where it comes from. (how do I know this? prior to my nursing career--I paid my way through college as a paralegal for a medical malpractice firm, and I saw quite a few nurses regret not having their own malpractice insurance).
Something else to think about is the fact that if a suit were to arise and you are still employed with your employer, you are going to be represented by your employers attorney, who I'd be willing to bet is not going to be concerned with your future, only the future of your employer (who in most cases is a hospital). They will do just about anything to settle the case, regardless of what that might do to your license, they are NOT going to be looking out for your best interest, like your own personal attorney might be.
Thirdly--if you are a nurse that has really done something wrong, like a nurse that I once worked with, she was let go of just before a suit was filed against our hospital--so the hospital no longer had to cover her. She had no insurance...The hospital settled with the family, the nurse was still sued. I work in an employment at will state, so they didn't "need" a reason to dissolve her job.
For $50-$100 per year...I too, would never work a day without my malpractice insurance...I'm pretty sure my premiums are cheaper than what it costs me to renew my license each year...just a few things to think about...