do not follow more closely than reasonable and prudent having due regard FOR THE SPEED OF THE OTHER VEHICLE and of the TRAFFIC ON AND THE CONDITION OF the highway. 21-310, transportation article, annotated code of maryland, (emphasis added).

i would think the officer, at trial, must enter some testimony of the speed of the vehicles and/or the condition of the highway (ie, snow, wet, etc.) in order to sustain a conviction.

of course, what the judge had for breakfast can also be a factor.