Parents should be able to legally withdraw their child from SATs, if they recognise that their child is suffering from the detrimental effects of SATs, or that they simply do not want to subject their child to the unnecessary stress associated with such testing.
You may be interested in these active petitions
SATs at the end of a child's primary education serve no purpose other than to provide data with which to show a primary school's 'worth', and also perhaps on which secondary schools can base their unrealistic targets for GCSE grades.
However, subjecting 10 and 11 year olds to such punitive testing is highly stressful and can be hugely demoralising. It has been reported that year 6 pupils have been known to suffer from insomnia and other stress-related conditions. Parents should have the choice.