Charged With Unsecure Load At The Landfill Site

Is the ticket nullified since I was not on a road or highway? They set up a trap in the landfill site, are they charges still applicable?

Just curious to see if the police sets up a trap on city property, if that falls under the highway traffic act

As long as the police observed the vehicle on a highway and come into a parking lot where they are parked an offence notice can be issued.

Are you sure you were charged under the Highway Traffic Act? Some municipalities have bylaws that mirror the highway traffic act, with offences like speeding, disobeying lights and insecure loads. It's typically bylaw officers that enforce them, but they will do things like run radar at the City dump and charge people with various offences similar to the highway traffic act.