What Are Political ‘Surgeries’ in Britain?

David Amess, a British lawmaker who was stabbed to death on Friday, warned in a book published less than a year ago that attacks on members of Parliament had spoiled “the great British tradition” of voters meeting politicians, adding that a deadly assault “could happen to any of us.”

That tradition of lawmakers conducting regular, in-person meetings with voters — encounters known as constituency surgeries — gives Britons unusually good access to their political representatives.

But Mr. Amess died after being attacked at just such an event on Friday, and in 2016, it was outside a constituency surgery that Jo Cox, a Labour lawmaker, was murdered.

In 2010, Stephen Timms, another Labour lawmaker, survived a serious stabbing at another such meeting, and in 2000, a parliamentary aide, Andy Pennington, was killed in similar circumstances while trying to protect Nigel Jones, a lawmaker for the Liberal Democrats, from a machete attack.

Constituency surgeries are intended to give Britons the chance for a one-on-one consultation with their member of Parliament, an opportunity to air grievances or raise concerns much as they would with their medical physician. (In Britain, a doctor’s office is referred to as a G.P. surgery.)

Lawmakers feel strongly about close contact with those they represent because parliamentary constituencies are the bedrock of the British political system, with each member of Parliament representing one of 650 parts of the country. In constituencies where political sympathies are evenly divided, personal popularity can mean the difference between re-election and ejection from Parliament.

But the death of Mr. Amess has renewed debate about whether to take such meetings online, or to increase security, including possibly erecting barriers, to protect the politicians from the people they represent. Lawmakers invariably have at least one staff member on hand, but that has not always proved enough to guarantee their safety.

Some lawmakers see this kind of pastoral work as their primary role, including Mr. Amess, who spent much of his time in office concentrating on local duties. Usually, people are asked to email a request for a meeting, but constituency surgeries are often in public halls or churches, rather than at locations equipped with the security screening and metal detectors that the public must pass through if they have a meeting in Parliament.

And unlike some campaign appearances, surgeries are widely advertised in advance, giving notice to potential attackers of the specific whereabouts of politicians.

Death threats against lawmakers have risen in recent years, particularly via social media. And, though such attacks had taken place well before it, the Brexit referendum has polarized political debate in Britain. That vote provided the backdrop to the murder of Ms. Cox.