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Meet the undercover police hunting down sexual predators on the London Underground

They can spot the one person in a crowd of hundreds who is out to cause harm

One in ten Londoners experienced unwanted sexual behaviour on public transport.

But little known to the general public, there is a team of undercover police whose job is to identify, track and arrest criminals committing sexual assault on the London Underground.

Dressed in plain clothes so as to not attract attention, some officers have been working on the tube for over a decade, taking sexual predators off public transport and getting justice for the victims.

They've been trained to spot the one person out of hundreds on a crowded tube platform that is a risk to other travellers.

But how do they know who's up to no good? What do they do when they catch someone? And what happens when they get it wrong?

We spoke to an undercover police officer to find out.

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What is the most common type of sexual assault committed on the tube?

Most of the contact-type offences on the underground are typically some type of pushing against the victim. And it might be the hand or the back of a hand or it might be the groin area. There are offences where people may masturbate openly onboard a train, but without approaching, engaging with or touching anybody.

What is the typical working day like for an undercover officer?

"Proactive officers" are out all the time looking for offenders. If we’ve got a particular offender on a particular route they will be given information to go and look for a particular person. Or, maybe we’ve got CCTV of someone so we'll go and look for them along the travel routes they usually take.

Ultimately we want to be making arrests. Our goals are taking the person off the network so they can’t keep offending, and getting justice for the person that has reported the offence.

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It's not all working off leads, sometimes they're just patrolling right? How do you know who to look for?

If you ask an officer what it is they look for they probably couldn’t tell you, it’s just a feeling that they get. They're looking for the person who isn’t doing what everyone else is doing.

So you may have a few tourists on that platform figuring out where they're going, then you've got all the suits with every single one of them either looking at their phone or reading the paper.

And then your eye might catch the one person who isn’t doing what everyone else is doing. They’re separate to everyone, stood at the back of the platform, not looking at when the next train is coming in. Not reading a paper. Their eye level might be different. They might let a few trains go through.

What happens after you've identified someone as potentially being dodgy?

The officer will keep their eye on that individual and see if anything develops. The aim being they won’t let it develop to the point of an offence being committed but sometimes it’s very busy and by the time they’ve grabbed hold of the person they’ve already committed the offence. But they’re taken out of "the game" as soon as they possibly can be, so to speak.

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If they haven't committed an offence but you're suspicious, what do you say to them?

All you can do is explain your suspicions. We can speak to anyone but they don’t have to speak to us, they can just walk away.

Typically, the officer would approach and say something like “Look, I’m a plain clothes officer, here’s my identification, I’ve been here for the last 20 minutes to half an hour, you’ve let every single train go through to every single route, you haven’t checked your watch once, you haven’t checked your phone once, you’ve made no attempt to travel, your eyeline is all over women and only women, what’s going on?”

You might not be able to prove any offence, but you can certainly get a photograph of them for intelligence, get their details, and then investigate whether they've committed any other offences.

What happens when you get it wrong? Do you ever get it wrong?

Every single officer will raise suspicions at some point and be speaking to the individual only to find out they’ve done nothing wrong. We're just human too, so you know, you'll apologise but you’ll still explain your reason why: “The reason I was suspicious of you was because of this, but what you’ve told me makes perfect sense to me, thank you for your time."

They obviously can complain but it’s the way you deal with people. Most people will be fine.

There was a guy at Euston once, when I was working in the pickpocket team who operate in a similar way to the sexual assault team, and he was going up very closely behind people, low eyeline, acting strange. But it turned out he just had really bad vision. He didn't carry a stick, didn't have a dog, but when he pulled his phone out the screen only had two or three letters on it so he could see it. He wasn't looking at people's bags, he was looking at the floor to see where he was going!

Most officers will just get a feeling that something isn’t right, and on most of those occasions it tends to be the case that indeed something isn't right.

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What time of day do most offences occur?

The peak times are the rush hours, and that’s the time of day that lends itself to the offenders. It makes it, I suppose not easier for them, but that's when there is the most contact with other people. So, the offender almost needs to recreate that innocence, say if it’s sexual touching, that innocent touching but you can’t really do that when it’s quiet, so there’s no opportunity for them.

Does it vary at all depending on the time of year?

Typically, the summer months are when we see increases in offending so they’ve got to be down there.

Is that because of what people are wearing? As bad as that is to say

Yeah, what people are wearing. And that’s a really sad thing to have to say because you should be able to wear absolutely anything you want and the last thing we’d ever ever want to do is say to women “you shouldn’t wear this”. That’s beyond ridiculous, it’s the offender’s behaviour we want to change not the victims.

The mondayest monday. #crushhour

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Do you think if you guys weren't doing your job the majority of offences would go unreported?

It is an improving picture, we are seeing increases in reporting, definitely, and that’s something that we’re actively encouraging. The biggest thing for me is that people who come forward will be taken seriously.

Sometimes the victims talk the situation down so they can rationalise it in their head. So they’ll say “It’s okay it was only ‘a touch’” and there’s no such thing as only a touch, if it feels wrong it tends to be wrong.

Do you think all the publicity surrounding sexual assault recently has led to an increase in people reporting offences?

We definitely saw an increase around that time when that story broke [Harvey Weinstein]. We’d also had a few approaches prior to that from the BBC, and Channel 5 did a piece on their evening news, so it’s hard to say it definitely was just that. But we definitely did see an increase in reporting over those few weeks.

What do you think it will take for society to change so this crime isn’t being committed?

I think through education it's something that we can tackle. If you think about what were accepted forms of contact back in the 70s we’re in a very different place already now.

Some of the older offenders are set in their ways, we’re never going to be able to educate them, but then that’s for me to deal with those people and put them away when I can to stop them offending.