It is quite unlikely to be charged as obviously it is not good use of public money.
There is an offence of assault by apprehension but then you have to apprehend an immediate assault.
There is an offence of S5 public order where you have to be caused harassment, distress or alarm but that is fairly rarely prosecuted now.
S4 public order is more serious and not really relevant here.
Can I clarify anything for you?