A method of designating first and second transaction time stamps and first and second picture time stamps in a toll system as anomalous, the method comprising: accessing a first toll transaction entry, the first toll transaction entry designating a toll transaction between a first vehicle and the toll system and the first toll transaction entry including a first transaction time stamp; accessing a first picture time stamp associated with a first toll transaction picture deemed to depict the toll transaction between the first vehicle and the toll system; accessing a second toll transaction entry, the second toll transaction entry designating a toll transaction between a second vehicle and the toll system and the second toll transaction entry including a second transaction time stamp, wherein accessing the first and second toll transaction entries comprises receiving the first and second toll transaction entries from a lane transaction system; accessing a second picture time stamp associated with a second toll transaction picture deemed to depict the toll transaction between the second vehicle and the toll system, wherein the first and second toll transaction pictures are from an imaging system that is independent from the lane transaction system; calculating, using at least one computer processor, a transaction time difference between the first transaction time stamp and the second transaction time stamp; calculating a picture time difference between the first picture time stamp and the second picture time stamp; comparing the transaction time difference to the picture time difference; and designating the first and second transaction time stamps and the first and second picture time stamps as anomalous if the result of the comparison is above a predetermined threshold. accessing a first toll transaction entry, the first toll transaction entry designating a toll transaction between a first vehicle and the toll system and the first toll transaction entry including a first transaction time stamp; accessing a first picture time stamp associated with a first toll transaction picture deemed to depict the toll transaction between the first vehicle and the toll system; accessing a second toll transaction entry, the second toll transaction entry designating a toll transaction between a second vehicle and the toll system and the second toll transaction entry including a second transaction time stamp, wherein accessing the first and second toll transaction entries comprises receiving the first and second toll transaction entries from a lane transaction system; accessing a second picture time stamp associated with a second toll transaction picture deemed to depict the toll transaction between the second vehicle and the toll system, wherein the first and second toll transaction pictures are from an imaging system that is independent from the lane transaction system; calculating, using at least one computer processor, a transaction time difference between the first transaction time stamp and the second transaction time stamp; calculating a picture time difference between the first picture time stamp and the second picture time stamp; comparing the transaction time difference to the picture time difference; and designating the first and second transaction time stamps and the first and second picture time stamps as anomalous if the result of the comparison is above a predetermined threshold.