The agent waited in the dark outside Labour MP Andrew Little's Wellington house and surprised him when he got out of the taxi with the words: "There's no fries with that but you've been served".
The list MP has now had defamation proceedings served on him on behalf of ACC Minister Judith Collins. His colleague, MP for Hutt South Trevor Mallard, is expecting to be served any time.
The pair last week laughed off letters from her law firm Morrison Kent and a third attempt to get them to co-operate and apologise for comments Collins claimed defamed her by linking her to the leaking of a letter from former National Party president Michelle Boag about a privacy breach by ACC.
Little last week invited Collins to send "thuggish characters" and last night a process serving agent was waiting for him when he got home.
"It was dark, the guy leapt up and shined a torch in my face and served me with the papers, so fair cop."
There was an unwritten law that politicians didn't bother each other's families, he said.
"I was pleased they didn't come inside the gate, they didn't hassle my home, that's what I was most worried about.
"I think Judith Collins came very close to the mark. As it was the guy was sitting just outside our place, and lying in wait for me to get home."
Little said he would be consulting with his lawyer today and be releasing details of the case to back up his and Mallard's claim they had done nothing wrong.
They would show Collins had refused to answer questions in Parliament about the leaked letter and the MPs were doing their job by trying to hold her account.
"To the extent that her reputation is based on her being a straight shooter in Parliament, there is evidence to the contrary of that and I want to get that out sooner rather than later so people can see exactly what it is she is on about."
Little said he was convinced Collins wouldn't want the matter to go to trial she would be forced to defend her personal reputation.
A spokeswoman for Collins said the minister would not be commenting on the matter.
MPs cannot be served papers inside Parliament and Mallard said he would be surprised if wasn't served soon.
"I'm in and out of the building five times a day. I'm not hiding, I'm around."
But he had a warning for any agent who waited for him at home.
"It does get cold in Wainui."
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