Source: New York Times Source: The Independent I don't know if an entire state supreme court has been impeached before. We have had only one impeachment from the US Supreme Court, I think. US Supreme Court Justice Samuel Chase, a signer of the Declaration of Independence, was impeached in 1804 but was acquitted by the Senate. In 1969, Abe Fortas resigned from the US Supreme Court under threat of impeachment. He was accused of financial improprieties.
The fact they were impeached doesn't mean they will be removed. It might be a warning shot, however, telling them to get back into line and stop legislating.