Knife crime surged in London again in February 2018, such that London’s murder rate in that month (15) surpassed New York’s (14), and it got worse in March (22 murders) – a surge since 2014 of 38 percent.

Another accelerating violent crime is the use of acids in attacks: consequently, by 2017, Britons suffered more acid attacks per capita than any other nationality – the rate tripled from 2012 to 2017.

Police stopped using their legitimate powers to stop and search subjects in 2014, when the then Home Secretary (Theresa May) followed the fashion from America to curb the powers, given criticisms of their apparent racism (white people are less likely to be stopped than black people), even though racism is not the best explanation.

In 2014, May made a speech claiming black men are seven times more likely to be stopped and searched, knowing that the Home Office had shown whites were more likely, once controlled for local demographics and propensity to be on the streets at peak times – her dishonesty wasn’t exposed until 2018. May effectively put the fashion for looking strong against racism ahead of the declining fashion for looking strong against crime.

Although May talked the talk of being tough on crime, she offered few reforms, and her reforms were tweaks of prior policies or programs. Now Britons are reaping the whirlwind of complacency and deceit. The number of searches fell in 2016 to the lowest level since 2002, when violent crime was falling. Meanwhile, violent crime surged by 18 percent from 2014 to 2016.

In April 2017, the Metropolitan Police publicized the accelerating rate of almost all crimes, especially violent crimes using guns and knives. However, the Met was complicit. What did the Met blame? Not policing practices – it blamed cuts to funding and weak legislation. These are red herrings, diversions from failures to enforce current laws.

Then what happened? The police belatedly enforced the law against carrying knives, but not other weapons. Criminals were already used to carrying weapons, so, when they found knives riskier to carry, they searched for a weapon for which the police were not looking: acid.

In early July 2017, the Metropolitan Police and local politicians publicized the increase in acid attacks. The issue received more attention on 13 July 2017, when two teenagers used acid to attack a moped rider before stealing it to find other moped riders to attack with acid – at least five men were injured. Local politicians and the Met called for more legislation in order to restrict the purchase and carriage of acids.

In fact, such legislation would be impractical and unnecessary: the police need to enforce current statutes that already criminalize the carriage of any material as a weapon, without criminalizing the purchase of the sorts of quantities and concentrations of acids that are perfectly acceptable for use in cleaning.

A couple weeks later, a leak revealed that in the first four months of 2017, at least two of Britain’s police forces had increased their use of stop-and-search powers in response to violent crimes.

In August 2017, the current Home Secretary (Amber Rudd) signalled her support for an increase in stop-and-search checks, without blaming her predecessor (May).

In March 2018, the chief of the Metropolitan Police (Cressida Dick) committed an unadmitted u-turn. She got in the habit of giving interviews lamenting the loss of stop-and-search powers, and referring at length to how officers are over-cautious in their willingness to use probable cause as justification for stopping and searching, particularly a person of colour.

Another u-turn of March 2018 was the government’s decision to refuse to extend the contract of the Director of Public Prosecution (Alison Saunders) who took office in November 2013 with an explicit agenda to prosecute more men for sexual assault whatever the evidence. By the time the government finally took action, every rape case in the country was under review given the collapse of four rape trials in two months when the Crown Prosecution Service disclosed exonerating evidence just days before the final hearings. Ironically, she failed to curb organized, racialized abuse of under-age white girls; and she did not respond to the rise in violent crime effectively.

At the same time, the chief of the Metropolitan Police (Cressida Dick) revealed that she had told her officers no longer to believe automatically a claim of rape, but to keep an open mind.

Now, with the opportunity to appoint a more sensible Director of Public Prosecutions, and a more honest Metropolitan Police Commissioner, the government has its best opportunity to release the fetters on existing stop-and-search powers.

Stop-and-search is preventive. Searching on probable cause is reactive – it predicates that the police establish a reason to search: that reason is usually suspicion of a crime, which has two conditions: a crime could have occurred already, by when the intervention is too late for the risks except to prevent future crime; and the police must be in the rare situation to have observed the crime sufficiently to count as probable cause, which suggests that the risk-reward balance favours the criminal.

I understand the downsides, I am not denying the downsides – such as discomfort with interventionism in general and the inevitable disproportionate intervention in certain demographics, but this is an imperfect balance, and the balance has swung the wrong way, such that police in London are accused of racism for searching people of colour in districts of colour, and are under instructions not to chase moped-borne criminals, for traffic risks to the muggers.

The main block to stop-and-search powers remains Theresa May, who rose from Home Secretary to Prime Minister in 2016 without repudiating her record. Now she’s in dispute on this issue with Boris Johnson (her Foreign Secretary, and former challenger for the leadership), so the issue is loaded with implications for the ultimate political job in Britain and thence all other policies.

However, if we can be permitted to isolate stop-and-search from the political issue-linkages and fashions, stop-and-search is a good response to the current surge in violent crime, if applied without discrimination except to risk.