Yes, the probation department can charge supervision fees when someone is on felony probation. However, failure to pay supervision fees is not a probation violation; any unpaid fees are turned into a civil judgment -- as if you'd been sued and lost -- when probation terminates.
It's usually around $125 per month, give or take a little bit depending on the county.
I have seen probation fees as high as $12,000 a year in a felony matter. However, your brother can petition the court to reduce his fees based on his ability to pay if probation will not reduce them internally. He should contact his original trial attorney to assist him in this regard or a criminal defense attorney of his liking.
Lauren K Johnson
Criminal Defense and Juvenile Law