The Liberal Democrats' compromise on control orders which means that people are still to be curfewed and tagged without charge is significant of itself. But it is also important for what it indicates about the political future of the coalition.

The unexpected bonhomie of last May's Conservative-LibDem negotiations was principally a function of the LibDems' volte-face over the speed of deficit reduction. But agreement on rolling back the state's role in the economy was matched by agreement on a whole raft of civil liberties issues. The Conservative and LibDem manifestoes were already in accord on scrapping ID cards, the National Identity register and the nationwide Contactpoint children's database, as well as on restraining powers of entry and ending the misuse of anti-terror laws. The coalition agreement also incorporated LibDem proposals to outlaw the finger-printing of children without parental consent, the storage of internet and email records and the restoration of protest rights, as well as firming up Conservative proposals to stop the holding of innocent people's DNA and to limit CCTV.

Thereby, for negotiator David Laws, in his book on the making of the coalition, "the economic liberalism of the Conservative Party" had been convincingly combined with "the social liberalism of the Liberal Democrats"; the rightward oranging of the yellows matching the progressive greening of the blues.

For the left, the deal promised (or threatened) the drawing of a new fault-line in British politics, with both varieties of liberalism on one side, and a sullen, authoritarian Labour statist rump left on the other. The fate of the civil liberties agenda is thus a vital matter for all parties, and it's timely that Max Rowlands (of the research group Statewatch) has produced an audit of how it's going.

He finds a long list of kept promises, on ID cards, ContactPoint, stop and search powers, libel law reform and the misuse of antiterror legislation. As of Tuesday, 28 days detention without charge has reverted to 14 days. While, adjacent to the civil liberties agenda, the Prevent programme has been abandoned and (despite the Tory manifesto), the Human Rights Act appears secure.

That said, there is much devil in the detail. As Victoria Brittain argues below, the new Terrorism Prevention and Investigation Measures retain much (though not all) of the existing control order system. In its response to the counter-terrorism review, Amnesty argues that the proposal to extend deportations "with assurances" could expose more people to the risk of torture in their countries of origin. The wider list of the coalition government's sailing to the wind of authoritarianism is considerable:

• As Clare Sambrook of End Child Detention Now set out in openDemocracy's OurKingdom, the new regime for detention of the children of failed asylum seekers (in "pre-departure accommodation") looks more like an amelioration than an abolition of the old.
• As Statewatch notes, biometric passports may have been abolished, but biometric permits for non-European nationals will remain.
• The government has backtracked on its promise to end the storage of internet and email records.
• Despite pledging to scrap medical records to which non-medical staff have access, such records have more than doubled since the coalition came to power.
• The repeal of section 44 of the Terrorism Act 2000 (stop and search) could mean increased use of the more legally constrained but geographically broad section 43 (under which a photogapher was detained for taking pictures of cadets near Buckingham Palace last summer).
• Wednesday's announcement recommended that the stop and search powers of section 44 itself are reintroduced in a restricted form.
• And much of the remaining civil liberties agenda - on DNA and criminal record retention, fingerprinting children and CCTV - still awaits the publication of a Freedom Bill, which Nick Clegg promised would be out last November.

Coverage of the government's internals battles over civil liberties - including the impasse over control orders - has tended to emphasise its political impact on the LibDems. But it is just as revealing about the LibDems' coalition partners. The LibDems can justifiably claim to have made a difference, but that only goes to show they needed to. The resistance of the Conservatives to reform suggests that its much-vaunted commitment to social liberalism (and political liberalism too, for that matter) is skin-deep.

The danger is that Labour can't - or won't - exploit this opportunity. The party has moved on since the days when Diane Abbott was a lone advocate for Labour recapturing its traditional commitment to the noble tradition of civil liberties. But some Labour backbenchers are still trying to outflank the coalition to the right on crime, and the front bench speaks with an uncertain voice. Before his translation out of the Home Office, Ed Balls was attacking control order reform as putting politics before national security, and affirming his support for DNA retention and the current level of uncontrolled CCTV surveillance. This week, Yvette Cooper was evasive on how she'd reform control orders but definite on the need for legislation to put pre-charge detention back up to 28 days in emergencies.

If it genuinely accepts that it got it wrong on civil liberties, Labour should not be attacking the coalition on these issues from the right. Rather, it should be holding the government to account on its pledges, seeking to amend watered-down reforms, and insisting that the Freedom Bill fulfills its promise.

David Edgar is a playwright, this is an extended version of his recent article in the Guardian's Comment is Free

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