By Dylan Tokar

The last-minute trade deal between the U.K. and European Union has helped stave off a potentially turbulent disruption in key law enforcement and security priorities between the two sides.

The U.K.'s departure from the EU means the country has lost access to certain law enforcement tools and privileges available only to EU member states, including access to Europol, the EU's law enforcement agency. With the deal, which was approved by lawmakers late last month and took effect Jan. 1, the U.K. has attempted to negotiate new processes for handling crucial law enforcement activities such as cross-border information-sharing, arrests and extraditions.

Yet while the U.K. has avoided a more severe operational disruption threatened by a no-deal departure, the procedures spelled out in the trade agreement may, in many cases, increase the amount of red tape involved in cross-border probes compared with when Britain was part of the EU, lawyers say.

"Investigations are going to be slower, more painful, more expensive -- and arguably less successful -- than they were when we were a member of the EU," said Simon Airey, who heads the law firm Paul Hastings LLP's litigation and investigation team in London.

The loss of EU member-only tools and privileges poses a challenge in particular for the U.K. agencies tasked with investigating white-collar crimes such as foreign bribery -- a crime that they have been under pressure to tamp down on in recent years.

The U.K.'s Serious Fraud Office, which investigates and prosecutes major economic crimes, last year designated the country's exit from the EU as a strategic risk, saying the loss of EU tools could have an adverse effect on its work.

The SFO said last week that it would continue to forge relationships with law enforcement counterparts in Europe and elsewhere. "The trade and cooperation agreement contains provisions to ensure we and our European partners are able to continue working effectively towards our shared goals," the agency said in a statement.

The security and law enforcement relationship negotiated by the U.K. is similar to the one that the EU has with other non-EU countries, such as the U.S. In some cases, it outlines special privileges like those that the EU has granted to countries such as Iceland and Norway.

While the country is no longer a member of Europol and Eurojust, the EU's judicial cooperation agency, it will be able to place liaison officers and prosecutors within the two agencies to facilitate cooperation.

Among the most significant downsides for the U.K. will be the loss of access to real-time information through the Schengen Information System, a vast repository for law enforcement-related alerts and information.

In 2019, the system was accessed more than 600 million times by U.K. authorities, according to testimony before the U.K. Parliament.

The European system for arrest warrants and investigative orders that the U.K. previously participated in was designed to minimize protracted litigation and to speed up information-sharing and extradition.

The new agreement retains some of the limits for refusing requests for evidence, arrests or extraditions, but adds exceptions that could stymie others. The replacement procedures are likely to lead to an uptick in legal challenges, said Edward Grange, a lawyer at firm Corker Binning in London.

"I don't think it's a win for the U.K. in terms of mutual legal assistance because the system that's in place between EU members was a lot swifter," Mr. Grange said of the new processes under the Brexit deal. "That was the whole purpose of it."

But, he added, "it's not reverting back to a more cumbersome route, and there appears to be some carve outs for more streamlined communication." Without a deal, the U.K. and the EU would have reverted to European conventions dictating processes for arrests and extraditions that date to the 1950s.

The upshot of the collaboration enjoyed between EU member countries was on display last year when the U.K.'s SFO and France's financial crimes agency, the Parquet National Financier, reached a coordinated EUR3.6 billion ($4 billion) settlement with plane maker Airbus SE.

The U.S. also joined in the resolution, reaching a deferred prosecution agreement with Airbus in a federal court in Washington. The settlements resolved allegations that Airbus had paid bribes through intermediaries to win business in a dozen-plus countries, including China, South Korea and Russia.

The U.K. and French prosecutors were able to collaborate closely by forming a joint investigation team. The EU mechanism helped facilitate the flow of documents to the SFO while ensuring compliance with French data privacy laws, according to the agreements.

Under the Brexit deal, the future of U.K.'s participation in joint investigative teams is ambiguous. The agreement suggests that agencies such as the SFO may be allowed to join such teams on invitation by EU member states, but it makes clear that their operation must be governed by EU law.

It is too early to say exactly how the new relationship will work, but Mr. Airey, whose firm advised Airbus on its joint settlement, said the U.K. has the strength of its law enforcement's prior relationships with European counterparts to lean on. Mr. Airey wasn't personally involved in his firm's work on the case.

"We have to hope that the relationship that exists between the U.K. and the member states in the past could lead to the enhancement or renegotiation of the relationship in the future," he said. "That's to everybody's benefit."

Write to Dylan Tokar at dylan.tokar@wsj.com

Corrections & Amplifications

This article was corrected at 0009 GMT to reflect that the law firm Paul Hastings advised Airbus in the company's settlement with prosecutors. The original version of this article incorrectly said Simon Airey, head of the firm's litigation and investigation team in London, had worked on the settlement.

(END) Dow Jones Newswires

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