Local 1549: A little context would help

On the New York City subway, union Local 1549 has been running an ad complaining that the city is wastefully transferring police officers to desk jobs instead of putting them on the street. The ad states that a cop earns about $74,000, much more than the $37,000 that would be paid to a clerical worker to do the same job.

The union, which represents New York City clerical and administrative workers, is appealing to subway riders' sense of logic: wouldn't it be cheaper (and safer) to leave the cops on the street, and have civilians doing the desk jobs? Maybe not. If the city is trying to save money, it might be under pressure to cut payrolls. It doesn't want to let any cops go - that's politically controversial - so it hires fewer civilians and offers the desk jobs to cops. For the cops, a desk job is still probably better than no job, and the city does save money. But the clerical workers end up out in the cold... hence the ad.  Now, the union might be right when it suggests that the city is less safe with fewer cops on the street. Even if that's true, however, hiring more clerical workers might not be the most cost-effective solution.