Turns out it's not only possible - Lisa Sutter, the head of the MPD’s photo enforcement program, wants to bring crosswalk cameras to DC:
The D.C. police are hoping to install smaller, more mobile cameras in neighborhoods around town, catching drivers who fail to yield to pedestrians at crosswalks, block the box at intersections, or even fail to fully stop at stop signs, among other potential violations. The portable units would probably be battery- or solar-powered and affixed to small concrete pads set up around town, making them far more versatile than the permanent streetside cameras or cruiser cameras now in use. Their modest size would allow them to be used in areas where cameras couldn’t go before. [...]The new cameras could be on the streets this summer. Any chance we can get some over here in Northern Virginia?
The department would be continuously moving the cameras around to keep drivers guessing, and they’ll be accompanied by more signs telling drivers to obey the speed limit and stop for pedestrians. With the new technology, the units may be able to detect when a pedestrian has come to a crosswalk, then capture the plates of drivers who fail to yield. “I want to stigmatize [drivers] blowing past pedestrians,” Sutter said.
I do have to wonder: Has Lisa Sutter considered the alternative of giant cats?