Philadelphia prosecutors on Tuesday began looking for small-time marijuana possession cases to downgrade to summary offenses, in an effort to reduce court costs, officials said. Possession cases reaching the preliminary arraignment stage may be diverted from misdemeanor charges. People caught with 30 grams (a little more than an ounce) or less will still be arrested, but they could wind up taking a class, paying a $200 fine, and having their record expunged. The new leniency is expected to save taxpayer money that is spent on public defenders, police testimony, and documentation. District Attorney Seth Williams announced the change in April.