The Connecticut Post recently reported that the police department in Seymour, Ct., is jittery about potential liability issues that may arise from installing traffic calming measures like speed humps on a neighborhood street which is seeing heavy traffic and speeding. According to the article, the Seymour PD is concerned that “low profile” vehicles will sustain undercarriage damage and their owners will sue.

Liability issues have caused some municipalities to balk at traffic calming, but in practice these concerns have proven to be unfounded. A 2003 Transportation Quarterly article by Reid Ewing found that there had been only two successful lawsuits against traffic calming programs, one of which was overturned on appeal.

Connecticut (and New Jersey and New York, for that matter) have immunity by law for the design of road improvements and the decision to use traffic calming on a given street. True, if speed humps are designed so poorly that vehicles get damaged solely by driving over the calming device as intended, the town may be liable. Connecticut courts have used the words “totally inadmissable” and “obviously in need of correction” to describe such grossly negligent designs (the device above would likely be in such categories). Many states and municipalities have adopted design standards for traffic calming. Thanks to the design work of the Institute of Transportation Engineers and other groups, it should be easy for a town to build improvements – even old fashioned speed humps – that don’t cross the line from deterrence to damage and danger.

According to Ewing, governments can further protect themselves from liability by showing that traffic calming was installed in a rational manner: that government documented existing traffic problems, considered a number of alternate solutions, and performed follow-up evaluations of the traffic calming program. Agencies must also provide proper notice (i.e. signage) of calming devices which require drivers to slow down.

Given such immunity, local governments should be more concerned with liability issues that may arise from inaction. According to the Federal Highway Administration, an increasing number of cases are being settled where the responsible government entity identified a problem or dangerous traffic condition and chose to do nothing at all. Traffic calming is not the prescribed answer to every situation, but the government with knowledge of a dangerous traffic condition must reasonably react in some way. In Seymour, the town responded with increased patrols, speed traps, and new stop signs. These steps would likely be viewed as fulfilling the town’s duty and shield it from suit.