My brother got a divorce, what are his rights on getting a copy of his income tax and a copy of bank statement?

He can get his tax return and bank statements for the tax preparer and bank.

If it was a joint tax return, he is certainly entitled to a copy of the document. If his name is on a bank account, he is also entitled to a statement.

He should have gotten them before he got divorced. If she refuses to give him a copy, I suppose he could go to court and ask for an injunction to force her to give them to him.

The question is unclear as to who wanting to get from. His spouse is required to provide copies of all papers in possession upon request - informally as fiduciary duty - or through discovery. A consultation with an attorney can assist you with the selection of method best for your specific situation and preparation of necessary paperwork.

If his name is on those things, then he can easily obtain them from the bank and the IRS/State Treasury.

Your brother has a right to copies of his income tax returns irrespective of whether he is married or divorced. He does not have a right to demand a copy from his ex-wife if she has the only copy, but fortunately he can order copies directly from the state and federal governments. If your brother was identified as an account holder on the bank account for which he wants a statement, again, he has the right to go to the bank and request a copy of this information because of his status as an account holder. If the account in question is an account that was held only in his ex-wife's name, he has no right to a copy of her bank statements, and the only way to get that is by having the court ordered her to provide the bank statements to him if he can provide the court with a basis for doing so.