picking up the sister

its just gone past two in the morning and I drive into the local town, slowly and with extra awareness through the narrow roads, filled up with all sorts of taxis and cabs (you know the people carrier type) as well as many a police car. all the time far too well aware of the possibility of someone who has had too much to drink stepping out in front of me. I park outside 'baccus', where I am greeted by not one but two gentlemen relieving themselves. I switch the engine and the headlights off and reach for my phone to announce my arrival, my door is suddenly open and I am greeted by an officer of the law, I cancel the phone call I was about to make, take off my seatbelt and get out of the car.

bobby: 'you know that when your driving on the road, you are not allowed to see your phone' (takes my keys off the ignition, his comment leaves me thinking that maybe you are allowed to use your phone whilst driving off-road)
me: 'I wasn't using my phone'
b: 'my colleague saw you holding up your phone to your ear' (he knows how phones are used, he's one of the more intelligent ones)
m: 'I wasn't using my phone' (i'm secretly hoping repetition will do the trick)
b: 'well you are now holding the phone in your hand so I have reason to believe you were using the phone whilst driving, you do know that it is illegal to drive whilst on the phone'
m: 'I think you might be confused, I wasn't using my phone'
b: 'my colleague saw you on the phone whilst driving. what are you doing here?'
m: 'i'm waiting for my sister, i've come to pick her up'
b: 'have you been drinking tonight?'
m: 'no' (at this point I was looking forward to being breathalysed, having never experienced it before)
b: 'well we can't prove that you were using your mobile phone, just don't do it again' (hands me keys back and, along with the four other policemen that were standing around me, get in their van and drive off)

now there's nothing particularly remarkable about what happened, rather, it was how intimidated I felt whilst being accused, their minds more than made up. the possibility of believing me was never there.
the question that stays with me is 'why did they confront me if they could not prove it?' were they hoping for a confession? also to note: no ‘hello’ or ‘goodnight’

maybe one day.....