For the photo radar vans, It is determined by the law, 10 miles an hour over the posted limit. Then it has to be verified and signed off by the officer that was posted in the van.
For red light tickets, the infractions are determined by computer, then verified by a human. An officer from the jurisdiction then signs off on the infraction issuing the citation. In both cases they look to see if the driver is visible and attempt to verify if the gender of the driver matches the gender of the registered owner of the vehicle. When they can’t make a determination, a citation is not issued.

However, there are better ways to promote safety on the roads than punitive measures. These include LED Speed Limit signs (which the mayor mentioned), as well as warning flags on speed limit signs when there is a reduction in speed. There is also the general rule, supported by traffic engineers, of setting the speed limit at the 85th percentile of what speed drivers drive at. All three measures are proven effective, and don’t require punishing otherwise good citizens and hurting the perception of local government by the citizens (which photo traffic enforcement does).

In the end I won’t be shopping in Milwaukie, which is too bad for local businesses. I don’t feel safe around photo enforcement as it makes other drivers unpredictable, and I feel towns that use photo enforcement don’t use proper traffic engineering (too short yellow lights, speed limits below the 85th percentile, speed limits that go up and down for no apparent reason, poor signage, poor intersection and lane markings).

After Joe Rose’s article in the Oregonian, I made a ton of calls to ODOT and Portland Bureau of Transportation doing research and I think I made some people nervous when I pointed out the MUTCD rules, the 85th % speeds, and Oregon Revised Statutes. I was even researching if ODOT/PBoT was breaking federal law under MUTCD. In any case, they changed the limit. The 85th % speed on this street is 35-41 mph according to PBoT records. As long as the radar van keeps the margin of error at 10mph over, then people driving in the 85th % speed should be ok going forward. It is a tricky street.