PHILADELPHIA — Prosecutors want to send the longtime mayor of Newark, N.J., back to prison to serve more time for steering sweetheart land deals to a mistress.

But a lawyer for 74-year-old Sharpe James asked a U.S. appeals court to reverse his conviction.

James is in a halfway house finishing up a 27-month sentence after leaving prison this month. A jury convicted him of helping mistress Tamika Riley get the redevelopment deals.

Riley flipped the Newark land for a quick $400,000 profit. Prosecutors say a federal judge ignored those profits in calculating James’ sentence. They had sought a much longer term.

An appeals court hearing arguments Tuesday in Philadelphia asked if either side really wants to revisit the case.

James served as Newark’s mayor for 20 years.