Dartford suffered their third Skrill Premier defeat in four outings when they travelled to Luton on Tuesday night.
The visitors came under early pressure at Kenilworth Road but they reached the half-hour mark with the scoresheet still blank.
However, Luton then took the lead when Paul Benson headed home an Alex Wanless cross.
Elliot Bradbrook (pictured) missed a good chance to bring Dartford level and the Hatters promptly went up the other end and made it 2-0.
A deflection took Luke Guttridge's shot over Darts keeper Alan Julian and into the net.
Luton added a third goal midway through the second half when the excellent Lawless rounded Julian to put the result beyond doubt.
That result means Dartford have dropped into the relegation places and are now the division's lowest scorers with just five goals in nine games.
They host Kidderminster Harriers on Saturday (3pm).