Alan slept rough in south London. Toni, an outreach worker from my organisation, Thames Reach, met up with him most weeks. Over time she broke through his innate suspicion and painstakingly built up his trust.

Sometimes, with her help, Alan would move into a hostel, but never for more than a few weeks. His life was chaotic, dominated by heroin dependency which was remorselessly destroying him. Toni’s attempts to help him enter drug treatment were always thwarted by his mistrust of services and, she suspected, fear of failure.

Toni also had to contend with the countervailing forces drawing Alan back onto the street. The most powerful of these was the magnet of begging. Sitting outside Lewisham station, Alan was able to beg enough money in two hours to buy a wrap of heroin. There was never a shortage of local dealers prepared to do business with him.

Rough sleeping is an incapacitating existence. It took its toll on Alan’s health which, one winter, deteriorated alarmingly, culminating in Alan’s sudden, tragic, death from pneumonia. He died at his begging pitch, his body cradled in the arms of another rough sleeper.

Thames Reach’s outreach teams work across London every night of the year. Last year we helped 1,237 people find accommodation and stop sleeping rough. It’s challenging work. Almost 2,000 of the rough sleepers met and assessed by outreach teams working throughout London in 2016-17 were drug dependent, with heroin, crack cocaine and spice the dominant substances.

Outreach workers get to know homeless people very personally through nightly contact. Their resolve to help people off the streets is driven by their knowledge that sleeping rough can kill. Equally, an understanding of the impulses that lead people to beg means that outreach workers' responses to the tossing of coins into a proffered cup ranges from bafflement and resignation to outright anger.

The facts speak for themselves. On occasions when the police arrest people for persistent begging, more than 70 per cent routinely test positive for crack or heroin.

Many homelessness charities, including Thames Reach, have supported campaigns asking the public not to give to people begging. Instead, we have encouraged donations to be made to local charities or, where a person is believed to be sleeping rough, for a referral to be made to the StreetLink website so that the person can be assisted by an outreach team. These are primarily public awareness campaigns.

Yet the public’s propensity to give money to people begging seems undiminished. Too often, we witness situations where former rough sleepers are making progress in tackling an addiction, but are sadly overwhelmed by the temptation to return to the street to beg for drug money.

It is perverse that as Christmas approaches and the largesse of the public swells, we must be especially vigilant because of the increased risk of overdoses among people begging on our streets. When we say to the public, “your kindness can kill”, we mean it.

Recently the New Statesman website ran an article entitled “Why you should give money directly and unconditionally to homeless people”. The glib nihilism of this piece, which singled out Thames Reach for criticism, was shocking, encouraging the kind of mindless giving that works so powerfully against the efforts of outreach workers. Its casual bleakness was best illustrated by the approval given to the sentiment (spoken by the founder of User Voice, a charity staffed by former addicts) that “if your money funds the final hit, accept the person would rather be dead“.

To witness the death of people through overdoses, knowing they have bought the drugs primarily with money raised through begging, as we have at Thames Reach, is devastating for our staff. Indeed, the article was a kick in the teeth for all the committed teams from homelessness charities working directly with street homeless men and women who will not acquiesce to the inhuman fatalism which assumes there is some kind of deathwish gripping people begging to buy drugs.

It doesn’t have to be this way. More than 50 of my colleagues are former homeless people, some of whom were previously drug or alcohol dependent. They are now impressive role models, transforming lives for the better. We must help many more people to escape homelessness, complete treatment programmes and address the complex underlying issues that have led them to become drug dependent. There is help, there is hope and, most importantly, there can be life.

Jeremy Swain is the chief executive of homelessness charity Thames Reach