Tory MP David Davis—an outspoken critic of Theresa May's push for greater online surveillance powers, who is currently suing the government over the Data Retention and Investigatory Powers Act (DRIPA)—has been appointed as the new prime minister's secretary of state for exiting the European Union.

Davis, who is MP for Haltemprice & Howden, is a strong eurosceptic and has a consistent record of fighting government surveillance. In 2008, when he was shadow home secretary, he resigned from the House of Commons in order to stand on a platform of defending "British liberties."

His legal assault, alongside Labour deputy leader Tom Watson, on the UK's 2014 DRIPA law began in June last year, when the MPs challenged the law in the High Court in London. In July 2015, the court found that sections 1 and 2 of DRIPA were "incompatible with the British public’s right to respect for private life and communications and to protection of personal data under Articles 7 and 8 of the EU Charter of Fundamental Rights."

The UK government appealed against that ruling, and Court of Appeal judges sought clarification from the EU's highest court, the Court of Justice of the European Union (CJEU), last December. The CJEU heard the case in April this year, and is expected to release its judgment any day now.

Open Rights Group executive director Jim Killock told Ars in an e-mail exchange that the case at the CJEU won't be affected by Davis's elevation to the new post of Brexit chief. Killock said: "it has been referred, the hearings have taken place, and most likely the judgment has been made and is winding its way through the translators as we speak."

Moreover, DRIPA is due to be replaced by the Investigatory Powers Bill—which is currently winging its way through parliament. It would mean that non-compliance with the EU Charter of Fundamental Rights will need to be challenged afresh. Killock noted that, in a post-Brexit world, the constitutional implications of this course of action are important:

It will be unclear how CJEU judgments affect the UK post-Brexit, but the obligations continue while we remain. However it would be sensible for the government to minimise the risks of conflict and political controversy with the EU, as it may weaken their negotiating hand to be involved in serious disputes or worse, treaty non-compliance. The big question is what attitude the negotiations take to being part of the Single Market, what legislation would need to be in place, how the courts in the future would need to regard EU/EEA law. This may be reduced, or even frequently irrelevant, but there is no clarity on this.

Killock doesn't think that Davis's new role negotiating the terms of Brexit will impact human rights within the UK directly, but says that the two will certainly be intertwined: "human rights compliance will be a feature of the negotiations in general terms. The EU needs to consider its Charter obligations as it reaches any trade agreement, including with the UK."

That view is shared by Privacy International's executive director Gus Hosein. He told Ars: "The largest challenge going forward is that [Davis] will have to face head on the question of protections currently provided by European law.

Hosein added: "As we withdraw from the protections provided by the Charter of Fundamental Rights, this government and parliament have to think about whether for the purpose of trade we provide meaningful protections to all citizens and consumers in the UK, currently in instruments like the EU Data Protection Regulation and the e-privacy directive. Otherwise, we will forego fundamental rights and are left at risk of abuse by companies and government agencies."

On the issue of Davis' appointment as secretary of state for Brexit, Hosein said: "The risk is that we’ve lost an independent voice in parliament on the IP Bill. Though he’s now within Cabinet, his voice will be challenged by the surveillance hawks, including the prime minister herself."

Human rights' pressure group Liberty declined to comment on Davis' new cabinet position or his fight against surveillance when quizzed by Ars. We also sought comment from Tom Watson, but he was yet to respond to our e-mail at time of publication. Ars will update this story if we do hear back from Labour's deputy leader.