tax credit and public funds

hi all

I wonder if anyone can help....

I currently get working tax credit and I want to sponsor my wife for settlement visa into the UK. (I am a British Citizen).
I have read in this forum that tax credit counts as a public fund but it does not have any effect on the entry clearance process because it is ok for me to recieve tax credit not my wife. I have talked to a solicitor and he was saying that he is not sure if this will have any adverse effect on the visa or not.

Is it ok for me to apply and tell them that I am in reciept of tax credit or not? Will it have an adverse effect on the visa? Can some one quote me a government document where it says that tax credit is not counted (for this case) as a public fund?

Please help and it would be appreciated.

cheers