The BAE judgment is just the latest in a string of policy decisions taken when Tony Blair was in power to be declared illegal.
While the question of the Iraq invasion's legality continues to cast a shadow, elements of the Blair government's counterterrorism, immigration and pensions policies have all been thrown out in recent weeks by judges.
This week an important part of the anti-terror strategy – to expel terror suspects to their home countries – was dealt a fatal blow by the Court of Appeal. Ministers had negotiated guarantees with Jordan and Libya that people sent back would be well treated. The court found these promises to be worthless.
In December 2004 the House of Lords found the "draconian" detention of foreign terrorist suspects was illegal. The Blair government responded with control orders, which put strict controls on suspects released into the community. They too have run into trouble, most recently when the House of Lords ruled last October that the 18-hour curfews were a deprivation of liberty.
The Blair government was dogged by court reversals over its asylum and immigration policy. On Tuesday the High Court found changes to visa rules for skilled migrants amounted to "conspicuous unfairness and an abuse of power".
Last month three Appeal Court judges upheld a ruling that the Government misled 125,000 people who lost their pensions when their companies became insolvent. Government leaflets had encouraged people to join company pension schemes without mentioning the risk involved.Reuse content