The deputy prime minister denounced those spreading bogus and false allegations of child abuse on the internet saying they were going to harm the cause of justice for victims, while on a trip to Ireland.
Clegg also declined to openly criticise a group of Tory MPs who are calling for statutory legislation to deal with the media after Lord Leveson completes his report into press standards. But he added that any new system of press regulation should be "independent of politicians obviously".
Speaking in Dublin after a meeting with his Irish counterpart, Eamon Gilmore, Clegg said he was concerned over the way McAlpine had suffered false allegations in connection to the north Wales care homes abuse scandal.
"The revelations that have come to light today, it is difficult to exaggerate how horrific they are. It is immensely important that the victims feel that they can have confidence, that they can break the silence, that they can come forward which is an immensely painful thing to do if you suffered sexual abuse many years ago. They need to feel there is a proper process which looks at those allegations seriously.
"That's why I am very concerned that what we are seeing today instead is trial by Twitter. That's not right by the victims and it's not right by the principles of due process or fair justice."
He said that the inquiries being set up after the Jimmy Saville scandal broke "must be allowed to run their course and in the meantime it's really important we don't have people jumping to their own conclusions without seeing the full facts".
On the media in the post-Leveson world, Clegg said: "Everyone agrees there is a problem, the status quo is not working and all of us need to be able to look Millie Dowler's parents and other victims in the eye, and say, 'Look in the future there will be a proper independent system of recourse and accountability when things go awry.
"Now I don't know what Lord Justice Leveson is going to impose but I have some sympathy with the view that the test should be whether any of the arrangements are properly and permanently independent. Independent obviously of politicians who seek to influence and impose themselves on the press but also for this to be independent of the press. That was something highlighted in the letter from Conservative figures to the press this morning."
Clegg also praised Ireland's handling of the recession and eurozone crisis, and predicted that the Republic was on the road to recovery given that its exports are up 10% this year.
guardian.co.uk © Guardian News and Media Limited 2010
image: © Liberal Democrats