Clarke's comments come in the wake of the club taking disciplinary measures against Liam Ridgewell after inappropriate images of the Baggies left-back appeared in a Sunday newspaper and on the internet.
Albion boss Clarke said the matter had been dealt with "internally" and the incident had no bearing on his decision to sanction a Christmas outing for the players.
He said: "As far as we are concerned, it is closed and we moved on. Has Ridgewell been sanctioned? The matter has been dealt with internally. I don't want to talk about it.
"If the players want to organise a night out, then I've got no issues with that.
"You expect the boys to go out and have a good night together, spend a bit of time in each other's company, have a laugh and a joke and behave themselves. They are grown men, they are not children."
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