Guelph Police say a convoy of vehicles followed a suspected impaired driver on the Hanlon until they arrived.
Officers say a call came in Friday night about an erratic driver believed to be under the influence near Stone Road.
Several other motorists were able to work together to stop the suspect vehicle in a safe way near the Wellington Road off-ramp.
Police say they received reports that up to 10 vehicles were driving behind the suspected impaired driver all with their hazard lights on.
A 60-year-old Guelph woman has since been charged with dangerous driving, impaired driving and refuse to provide a breath sample.