In an annual effort to keep intoxicated or drugged motorists and other traffic scofflaws off local freeways and unincorporated roadways during the holiday, the CHP will conduct a 12-hour maximum enforcement period, or MEP, scheduled to begin at 6 p.m. Friday, during which all available officers will deploy onto freeways, highways and unincorporated roads throughout San Diego County and statewide, to nab DUI suspects and other lawbreakers.