National Party deputy leader Bill English is seeking legal advice after a well-known gay website published allegations about one of his five sons in a news story.
The article on GayNZ.com alleged that the unnamed son had been involved in posting abusive statements which carried homophobic overtones onthe popular Bebo networking website.
The news story quoted people who worked with groups for gay and lesbian youth as being shocked by the postings.
Mr English yesterday branded the news story a "disgusting and sick attack" on his teenager, and he questioned what types of activity were becoming fair game in politics.
"I expect any statement I make to be scrutinised - no one expects the same scrutiny of every comment by anyone on an open teenage social networking site," Mr English said.
"All family members of public figures should be alert to the fact that any internet activity is now fair game for politics."
Mr English's statement did not deny his son had been involved in the postings, but described the claims made in the news story as "unproven and potentially defamatory".
He said he was taking legal advice on the "unsubstantiated claims about the supposed views" held by his son.
A spokesman for Mr English said he would be making no comment outside what was in the statement.
GayNZ.com said it became aware of the Bebo postings when readers sent concerned emails about them.
It then referred the webpages to Mr English and his office but was told there would be no comment.
GayNZ.com went public with its story late on Monday, and Mr English issued his statement in response to questions from other media.
Social networking websites such as Bebo have been in the headlines in recent months as their popularity grows, particularly among young people.
Bebo was at the centre of the hunt for the killer of Auckland Grammar student Augustine Borrell this month, when users posted messages alleging who was responsible for the stabbing.
A judge later warned young internet users not to identify the man accused of murdering Augustine after scores of comments posted on the popular website about the case.
