The Bloomberg administration says that by arresting more than 350,000 people for having small amounts of marijuana since 2002, the police have helped drive down serious crime — and that the consequences for the people locked up have been minimal.

Nearly 90 percent of those arrested on charges of personal possession of marijuana are black or Latino, although its use by young white people is rampant in affluent quarters of the city.

Faced with criticism from members of the City Council and the State Legislature, aides to Mayor Michael R. Bloomberg have emphasized that few of those arrested on pot charges actually end up with criminal convictions because most cases are dismissed and sealed after one year. In effect, they say, the arrest process itself — which can stretch for 24 hours or more, under squalid conditions in holding pens — is the extent of the punishment.

Yet there are other, hidden consequences, say lawyers and advocates who work with those arrested. People regularly lose jobs for missing work as they wait to see a judge or because their employers do not want anyone connected with even minor drug offenses on the payroll, said Marlen Bodden, a staff attorney with the Legal Aid Society.