ThaiPBS had this slightly confusingly worded article:

Former Democrat party leader Abhisit Vejjajiva warned the National Council for Peace and Order to not introduce any broad-ranging amnesty law which will cover more offenders rather than the coup makers otherwise there may be chaos.

He pointed out that the last political conflict in this country was rooted in the attempt by some parties to introduce a wholesale amnesty for offenders of both political and criminal offences such as corruption and armed violence that many people found it difficult to accept.

Nevertheless, he admitted that it was a traditional practice for coup makers to introduce an amnesty law to exonerate themselves from being held accountable for the offences.

In his Facebook post in Thai it is clearer where he stated that in regards to the interim constitution that one thing that you cannot avoid is an amnesty provision for the NCPO because it is is the normal procedure of a change outside of the constitution (คงหนีไม่พ้นที่จะมีบทบัญญัตินิรโทษกรรมให้ คสช. เอง ซึ่งเป็นแนวปฏิบัติโดยทั่วไปเมื่อมีการเปลี่ยนแปลงนอกรัฐธรรมนูญ). Even if this is incorrect, but it is the reality of Thai society which has always been accepted, I hope that the amnesty will not benefit other wrong actions (ซึ่งแม้ว่าจะเป็นเรื่องที่ไม่ถูกต้อง แต่เป็นสภาพความเป็นจริงที่สังคมไทยยอมรับมาโดยตลอด แต่ผมหวังเป็นอย่างยิ่งว่า การนิรโทษกรรมนี้จะไม่เอื้อเฟื้อเผื่อแผ่ไปถึงการกระทำในความผิดอื่น).

BP:  The amnesty issued last year was one that Abhisit opposed and participated in street demonstrations against, but now an amnesty if it is for the military junta for suspending the constitution and removing an elected government, he calls it normal and the reality is that he is only concerned whether Thaksin will get amnesty.

btw, Abhisit refers to other wrong actions so by implication he is stating the coup is wrong….

P.S. The Democrats a group that is not illegal to criticize….