In 2000, the State of Maryland put an $8,997 lien on Mr. Martin’s property for unpaid taxes that he would not pay off till 2014, a sign of chronic financial difficulties. In 2003, he was charged with misdemeanor computer harassment, a result of pestering a woman with unwanted messages. The charge was eventually dismissed.

Mr. Martin has a history of “binge drinking on a monthly basis,” Judge Richard D. Bennett of Federal District Court said in a detention hearing on Friday. Alcoholism does not automatically block a security clearance, officials say, but the person must acknowledge the issue and seek treatment.

In 2006, Mr. Martin was charged with driving under the influence. In 2008, he cut off another driver and in the ensuing argument, announced that he was a police officer, according to two acquaintances who did not want to be named speaking critically of him. When it turned out the other driver was an off-duty state trooper, Mr. Martin fled. The local police charged him in the incident, but the record of the episode was later expunged.

“Those are all big red flags, and reasons why you wouldn’t get a clearance,” said Ross Schulman, a cybersecurity expert at the Open Technology Institute at New America, a Washington research group.