Gill-Webb denies using threatening words or behaviour, with intent to cause harassment, alarm or distress.
He also denies an alternative charge of using threatening, abusive or insulting words or behaviour or disorderly behaviour within the hearing or sight of a person likely to be caused harassment, alarm or distress.
More top news
Officers were given the touching letter at Brixton Station while they were on a reassurance patrol after yesterday's attack
The 52-year-old had previous convictions for violence but was not on the anti-terror watchlist.
In a statement Charlton Athletic said: Keith was a true hero who will be greatly missed by all the Charlton family and everyone at the club.