A marked police car hides at the entrance road to the biological warfare research buildings to the right of Gas House Pike heading west as you are entering the Frederick city limits. The police car cannot be seen until you pass the road on the right were he is sitting, and waiting. I have seen two cars pulled over by the police on two different occasions as well as having seen them park there at least a dozen times.
The speed limit is 45 MPH on Gas House road until you see a sign posted with a 35MPH speed limit as you cross the Frederick city limit. Most people are probably doing more than 50 when the get nailed.