From Bike Portland and I will highlight this bit:
"Given the circumstances, it seems like issuing a citation would probably not stand up in court. Any person could go in and say, ‘It’s dark, rainy, there’s this little red light in the road’. I think any judge would toss that citation out’.
…
It probably wasn’t powerful enough or large enough to overcome the circumstances surrounding this situation
…
I could totally see how you’d miss a small red light."
— Det. Sgt. Jim Shumway, Beaverton Police Department
[B’ Spokes: What bothers me is two fold. Why do we have legal requirements that don’t stand up in court? And just because there are some low end lights and reflectors, why isn’t there a standard that can be applied that can say that the cyclists meet or exceeded visibility standards in this situation?]
https://bikeportland.org/2011/02/15/beaverton-fatality-follow-up-a-conversation-with-police-spokesman-47980oldId.20110225142142176
Biking in Baltimore