There are few precedents for this sort of retrospective legislation.

此类有追溯效力的立法还鲜有先例。

There is no lack of precedents.

不乏先例。

There are few legal precedents.

这种情况少有合法的先例。

Yet the precedents are worrying.

之前的先例仍然让人担忧。

Yet these precedents were ignored.

但是这些先例都被忽略了。