The Grand Ayatollah Shobairi Zanjani answered a question about staff working for the business owners selling underweight.
Question: I work in a bakery and the owner of the shop tells me to under weigh the dough; considering that I have no other job, is it allowed for me to work in this shop and is my income Halal?
The Grand Ayatollah Shobairi: If this act means selling underweight or violating the condition for flour delivery and you sell the bread yourself, this act is Haram; as well as if you are the cause of the Haram act. Otherwise also if it is violating the law or causing violation of the law, according to precaution it is not allowed; otherwise, you have not committed a sin. Of course if the conditions are right, do prohibit from wrong.