In Macomb county in Michigan, "pay to stay" fees range from $8 (£4.34) to $56 a day, according to what an inmate can afford.

Former prisoners can go back to jail for not paying the bill or have their car seized by the local sheriff.

More than 40 states allow their jails to charge fees, according to the national institute of corrections.

The charges are popular with many, but campaigners for prisoners' rights say they place too heavy a financial burden on a group of people already poor and excluded.

Richard Blumenthal, the attorney general of Connecticut, told the New York Times: "Most inmates are not drug kingpins with lots of assets. In some cases, seizing assets may be counterproductive because it will interfere with their rehabilitation."

In many cases, the cost of collecting the fees also exceeds the amount recouped.

The Macomb county sheriff's department collected almost $1.5m in fees last year, and this week received its biggest single payment when the wife of an inmate serving six months for drunk driving handed in a cheque for $7,212.

The county's annual operating costs are $38m and the prison programme costs $120,000 a year.

"Why should we as taxpayers have to pay the whole cost of incarcerating these people who break the law?" asked Mark Hackel, the county sheriff.

Prisoners say the fees are steep for a shared cell and 2,800 calories a day.

De Juan Hunter, awaiting trial for receiving stolen property, told the New York Times that prison officials took $12 for lodging from the money he had on him when he was arrested.

"They are taking my money before I've been tried and convicted," he said.