The proposed code is being debated at Stormont
Northern Ireland Assembly members will have to register any family members they employ, after a new code of conduct was adopted.
MLAs will also have to register any money earned from outside work.
The code, which was proposed by the Assembly's Standards and Privileges Committee, was approved by MLAs on Tuesday.
The Standards committee will be able to recommend the Assembly suspends, without pay, MLAs who break the rules.
The rules also mean family members who are paid rent for constituency offices will have to be noted on the register.
A section of the code warns members to be careful about the manner in which they express their opinions - committee members say this could be used against any politicians expressing racist or homophobic views.
BBC Northern Ireland political editor Mark Devenport said: "The Standards and Privileges Committee has been working on this new code for some time, but its chair, Carmel Hanna, acknowledged that the Westminster expenses revelations about duck houses and moats had given the matter more urgency."
Last year when the issue of employing family members was first raised the DUP said 18 of its MLAs employed a relative, among UUP MLAs it was seven, among the SDLP MLAs it was 10 and among Sinn Fein MLAs it was three.