Yes, it's pretty much standard that a prospective new employer won't contact your current employer.

If I thought a previous employer was giving out bad references for me, two things come to mind.

First off, did you contact the employer and ask them if you can use them for a reference? Don't assume!

Then if you do feel they're leaving bad references, ask around and find somebody who can call them and ask for references. If you can find somebody you know who has a business, that's all the better. If not, just have somebody who can sound/act the part, do so. A buddy of mine was caught in this trap years ago, and it turned out his previous employer WAS giving bad references. To make it worse, the information he was sharing was 100% bogus. So he got an attorney to draw up a "keep this shit up and your ass is grass, and I'm the lawn-mower" letter, and it stopped. It turns it was a small business, and the office person who would answer these questions had a crush on my buddy, which he never responded to. So she responded to her hurt feelings by trying to fuck up his career.