THAT THE RANK-AND-FILE police officers in Prince George's County are upset is understandable - for their lot is not a happy one at all these days. As they are quick to point out much has happened to upset them. They do not enjoy a great reputation among all the people they serve; two of their most dedicated colleagues were fatally shot while in the Hyattsville stationhouse; another officer was fired from the force for fatally shooting a fleeing shopliftine suspect; and the force has been without a contract for the past year. Moreover, they feel that even their chief, John W. Rhoads, has not given them the support they deserve. But the sympathy the men seek surely pales in view of their current slowdown.

However justified the officers' grievances may be, they surely will not win their way into the hearts of taxpayers by deciding which laws will or won't be enforced. Union leader Laney Hester's ever-so-cute instructions have been calculated to please motoring scofflaws. But one or two traffic fatalities during this union-inspired amnesty for reckless drivers could spoil the game. Or let it come to the following situation, outlined by one officer after a burglar-alarm call: "If we wanted to we could have decided that maybe there was a burglar here and he was on the roof. So we'd have to call the fire board and get them to send a ladder truck. Then we could decide that a complete canvass of the neighborhood was necessary. We'd have to send for more units and spend an awful lot of time making a thorough check."

How classy. The officers should be aware of increasing evidence across the nation that the attempts of rebellious municipal workers to pormote health and public safety crises in exchange for imporved working conditions - be it in Prince George's or Memphis - are backfiring. Voters are getting sore at elected officials who cave in to such tactics. Even those officials elected with strong labor support have been winning strong constituent approval of their efforts to defend local budgets against heavy-handed union pressures.

The county should not ignore legitimate, responsible collective-bargaining efforts on behalf of its employees. In the public sector especially, there is a need for collective-bargaining alternatives aimed at preventing workers and managements from reaching desperate situations. But toying with law enforcement has no place in this process.