Sentencing Stephen Gough, judge Sarah Munro QC said: "This is a much more serious offence than the other public order offences. In those circumstances I take the view only a substantial custodial sentence is appropriate."
She said that Gough, who has been on remand, will be eligible for release on August 14 - one day after there is a hearing at Southampton Magistrates' Court to impose a full Asbo on the former Royal Marine.
The judge conceded that, if she had allowed Gough to leave by imposing a sentence commensurate with his time already served: "There is a reality here that he will walk out on these steps naked. I do not think I can ignore that reality.
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Mostly dry with sunny spells throughout the day. Some isolated thundery showers are possible in Kent this morning and feeling fresher
Sunny this evening, then dry overnight. There is the risk of thundery showers for Kent tomorrow morning, then sunny spells by the afternoon
Sunshine to end the day then dry tonight. Tomorrow will be mostly dry and feeling fresher with the risk of a heavy shower in the afternoon