Thing is, there are genuine children and teenagers who are being investigated and refused help because they are assumed to be adults, either because of their appearance or their demeanour. On the mature demeanour thing: if your mum has sent you off at 13 to travel to Europe, because she's terrified of you being recruited by the local militia now that you are tall and strong, and it's taken two years for you, travelling through god-knows-what, to get to a place where you can claim asylum, you will be years ahead mentally and emotionally of your peers who have had a more sheltered life, even while you are fifteen or sixteen physically.
And sixteen year olds can vary wildly in their appearances anyway. Plenty look like adolescents, still. Plenty look like men. My DS does - he's not white, he's over six foot tall, he has facial hair, and I am convinced that if he'd rocked up in the UK claiming to be 16, people wouldn't believe him, would think he's in his twenties.
Yes of course there are men trying to buck the system, because they don't want to be sent back, but don't go down the road of thinking that every refugee who says they are a child is lying. We are at serious risk here of throwing the babies out with the bathwater.