This week, D.C. residents learned firsthand the consequences of having their elected political leaders mired in scandal and facing possible criminal indictments. The lesson arrived in an unlikely manner: out of the debate over arresting the operators of vehicles with expired registrations.

This issue was raised last year. Despite heavy media coverage, however, neither D.C. Council Chairman Kwame Brown nor Mayor Vincent C. Gray, both of them serving on the D.C. Council at the time, suggested that the District’s long-established law should be reviewed, let alone changed. What a difference a year makes.

Then on Aug. 6, Fox5 ran another story on the subject, along with a considerable bit of rhetoric from AAA Mid-Atlantic. Other news outlets, including the Post, covered the story. Within a week, both Gray and Brown were pushing changes to the law. What changed? Both the mayor and the chairman are now under federal investigation and potentially face indictment. That makes them both politically weak, vulnerable and susceptible to pressure.

The pressure to change the law has not come from D.C. residents; it has come because well-connected nonresidents were arrested and didn’t like it. Just like last year, those few arrests have sparked tirades from AAA and a heavy media cycle on the issue. The only new element this time is a letter from Virginia Sen. James Webb (which, if it had been sent to scandal-free politicians, probably would have been characterized as an affront to D.C. independence).

Lost in all of this is the fact that the law in question is long-standing and effective. Hundreds of arrests have occurred over the years (most of them involving D.C. residents) without hue and cry. Such arrests are a valuable tool for tracking down criminals and ensuring compliance with the District’s motor vehicle requirements. If this law is such a travesty, where were Gray’s and Brown’s concerns as ordinary District residents were being arrested?

If Webb or any of his colleagues want to exercise their constitutional authority to govern the District with regard to public safety issues, the police union would be happy to have the added resources they could deliver. Generally, overall crime in the District is up 3 percent this year (the opposite of national trends), and we are down more than 400 police positions. For 10 years, the Seventh Police District in Ward 8, an area of less than six square miles with approximately 65,000 residents, has averaged more than 50 homicides a year. We need help. But focusing on a minor traffic offense is not help. It is meddling.

As for AAA, aren’t there more serious issues for it to focus on in the District? Let me suggest two: The District’s drunk driving enforcement program lacks the capability to do breath tests; and as a result of the loss of officers, traffic enforcement has become an afterthought on city streets. How bad is traffic safety in the District? Year to date, traffic fatalities are up 45 percent. Where has AAA been on that issue?

Regardless of whether one supports the law, this is not the way a D.C. law should be changed. If there is evidence that the law is unfair, ineffective or simply unpopular with residents, there is a process by which those issues can be raised and the reviewed. That did not happen last year when this issue surfaced — because there was no evidence and no push for change by District residents. The law is now apparently going to be changed because two individuals who are supposed to be leading this city have made themselves vulnerable to political pressure from both inside and outside the District.

Kristopher Baumann, Washington

The writer is chairman of the Fraternal Order of Police’s Metropolitan Police Department Labor Committee.