A controversial Liberal insider whose name has surfaced at the long-running B.C. legislature raid trial says the NDP are defaming him in their effort to win next month's election.

Patrick Kinsella's lawyer has sent a letter to the NDP, saying the allegations made about him and his involvement in the government sale of B.C. Rail are defamatory, malicious and false.

It's the first time Kinsella has responded to the allegation that he received $300,000 from the Liberals to help sell the Crown railway, while also collecting money from the eventual buyer and B.C. Rail itself.

The suggestion has prompted a feeding frenzy by the New Democrats in the legislature and on the campaign trail, with attorney general critic Leonard Krog demanding an RCMP investigation of Kinsella's role in the deal.

The letter from Kinsella's lawyer says he did not receive any money from the government, and demands a "clear and unqualified" apology within three days.

Leader Carole James says she's not going to back down from holding the Liberals and Kinsella accountable, while the Liberals have declined to respond to allegations, saying the case is before the courts.