The lethal "zombie" knife Joshua Gardner smashed against the window of a passing car had only one use - killing. And the dash-cam video of last May's incident in south London left no question about the teenager's intent - to do harm.
Yet, despite Gardner's attack being caught on film, he received only a suspended sentence, even though he was on the Met's gang list with a previous conviction for a theft committed at knifepoint.
As a youth worker I spent more than 20 years dealing with the Joshua Gardners of west London and know full well the circumstances that push them into crime.
But I also know what arguments work in keeping them away from crime.
Jail is one. And right now the thugs knifing each other in London don't fear the justice system. That needs to change.
Put simply, Londoners need a mayor who is tougher on crime. And while funding is certainly a factor it isn't an excuse to avoid action - you still have to crack on and keep people safe.
Yes, that means supporting families and creating better opportunities for our young people, but it also means prioritising existing budgets to maximise police numbers and drive down crime.
According to Government figures, criminals handed "soft" sentences over the past 11 years went on to commit a further 5.5 million offences. And people are angry about it.
The Attorney General's Office received 837 requests for a review under the Unduly Lenient Sentence scheme in 2016 - a 17 percent rise on the previous year.
People are losing faith in the system. I support mandatory jail time for adults caught carrying a knife for a second time.
The same goes for the perpetrators of acid attacks and moped-enabled crime.
While not the maker of laws, a mayor is still able to influence sentencing policy.
When elected, I will establish a unit that will object to sentences for violent crimes considered too lenient.
We need to have a society where it is once again the criminals who are under pressure, not our communities.
Originally published in The Express