In an effort to provide some context to the debate about whether roads are more dangerous since the legalization of marijuana, Colorado State Patrol said in a report Thursday that the number of citations issued for impaired driving with the drug fell slightly since the agency started tracking the numbers two years ago.In 2015, troopers handed out 4,546 citations for driving under the influence of drugs or alcohol, with 347 of them - or 7.6 percent - involving only marijuana.