If necessary, you may consider whether to instruct the head teacher to remain absent from school at times when tests are due to take place, while another person administers the tests
Very few people became school governors in order to engage (on either side) in this kind of political dispute. I cannot imagine that many governors will take this kind of action as it is quite likely to cause more disruption and damage to the children's education than any boycott of the sats as well as damaging the important relationship between Heads and their Governing Bodies.
Such highly confrontational action does not seem to be a sensible way to resolve such a dispute and indeed the National Governors Association (NGA) are urging caution and warning that such action might itself be unlawful. In a letter in today's Guardian the Chair of the NGA says:
As governors, we have been caught in the middle of a trade dispute between headteachers and the government. School governors do indeed have the responsibility of ensuring headteachers carry out their duties, but this does not necessarily give us the legal right to request those headteachers who choose to participate in the boycott to absent themselves from school. We have asked Ed Balls's department to supply us with chapter and verse on the legality of this, but we are disappointed that we have not received anything which satisfies us. The National Governors' Association does not support the boycott of the tests, but we need to be sure that the advice we give our members who are dealing with this very difficult situation is legally correct.
The NGA have published have published updated guidance for governors on their website and I would urge all fellow governors to read this before taking any action advocated by the Government and some LAs
In any event sats tests do seem to be going ahead in many schools pretty much as usual. Let us hope that whoever is secretary of state and the unions will both be willing to engage in a constructive dialogue about KS2 testing in primary schools.