"You don’t have to be a conservative to think it a bad idea to promote unionism in an economy struggling to climb out of a deep economic hole," says Judge Richard Posner. "You can be a Keynesian. ... Collective bargaining agreements, which are contracts between a union and an employer, usually forbid the employer to reduce wages during the contract’s term (usually three years). But the main reason why unions make it more difficult to recover from a recession or depression is that by raising an employer’s labor costs they cause the employer to lay off more workers in an economic downturn than if those costs were lower."