ST. PAUL — Minnesota voters have approved a constitutional amendment to hand power for setting the pay of state representatives and senators to an independent body.

Minnesota lawmakers haven’t approved a pay raise since 1999. Legislators often say they’re underpaid, but they’re also worried about a political backlash if they vote to increase their own salaries.

The state’s 201 part-time legislators are paid about $31,000 a year, though leaders make more. Allowances for expenses can bump that up an additional $9,000 or $10,000.

The amendment approved Tuesday sets up a group of eight Democrats and eight Republicans to decide pay raises. No members can be current or former lawmakers or state officials or their relatives.