The Intelligence Services Commissioner, Sir Mark Waller, gives Law In Action his first broadcast interview.
Sir Mark, a retired judge, is charged with judicial oversight of, among other organisations, MI5, MI6 and GCHQ.
It's his job to check the security services comply with the law when applying for warrants against individuals. Joshua Rozenberg asks him about the delicate balance between privacy and security, and the challenges created by Edward Snowden's revelations.
Also: why the County Court might not be the best place to solve disputes. We hear from a disappointed litigant and explore the possibility of resolving disputes online in the fashion pioneered by companies eBay and PayPal.
Following the collapse of a trial concerning sham marriages at a south London church in which immigration officers were found to have lied on oath and covered up evidence, Joshua speaks to Trevor Francis of Blackford solicitors, which represented one of the defendants in the case.
And is an establishment figure the right person to lead an inquiry into allegations of an establishment cover-up of sexual abuse? The journalists Andreas Whittam Smith and Oliver Kamm discuss.
Presenter: Joshua Rozenberg
Producers: Tim Mansel and Keith Moore
Editor: Richard Knight.