Spousal privilege

Spousal testimonial privilege (also called spousal incompetency and spousal immunity) protects the individual holding the privilege from being called to testify by the prosecution against his/her spouse/the defendant.

http://en.wikipedia.org/wiki/Spousal_privilege

薄熙来案件，配偶谷开来可以不出庭作证。但是中国法院非常乱，既然人家不出庭作证，你就不能用人家在庭外做的证词。结果中国法院用了谷开来的证词，薄熙来要当庭对证，中国法庭却拿出“配偶可以不出庭作证”为理由，拒绝了薄熙来的请求。这在美国是违反宪法第六修正案的，"in all criminal prosecutions, the accused shall enjoy the right…to be confronted with the witnesses against him."