It can be a challenge for major cities to keep their public transit lines safe, especially with limited resources.

In Washington, D.C., a series of high-profile assaults and shootings on the subway have led the D.C. Metro Transit Police to boost patrols throughout the system. But personnel numbers are tight right now, and even officers who have been confined to desk jobs due to injuries will be asked to monitor stations.

Municipalities deal with budget shortages by cutting spending on public services. However, sometimes these cuts can be more costly than initially expected.

Reducing public safety personnel can end up straining other budgetary line-items. For instance, in Orange County, Florida, a shortage of firefighters and strict federal overtime rules has led to a spike in overtime spending. The county has been forced to find $15 million in the last five years to cover this gap.

In an emergency, every second counts. But in far-flung rural areas, it can be difficult for first responders to reach their destinations in time.

Though municipal governments do their best to deploy emergency responders in a manner that gives them the maximum possible reach, tight budgets often leaves these crews understaffed. Public safety standards inevitably suffer as a result.