Armed with DNA evidence, authorities today charged a Maryland man in an 8-year-old sexual assault in which they say he left biological evidence on a womans bag and clothes while riding a crowded Green Line trolley in 2004 just two years after allegedly committing the same crime in Washington, D.C.

Timothy L. Day, 52, of Bethesda, Md., pleaded not guilty to one count of indecent assault and battery in Suffolk Superior Court, where he was released on $1,500 cash bail. The charges followed an eight-year, interstate investigation with Metro Transit Police officers in Washington, D.C., who were investigating a similar offense in their subway system in 2002.

Prosecutors said a 23-year-old woman was riding an outbound B line train June 22, 2004, when a man now identified by authorities as Day boarded the train packed with fans heading to a Red Sox [team stats] game. The victim told police the man was pressed up from behind her onboard and when she exited the train at Kenmore station.

Police later obtained a DNA sample from her shoulder bag, which was run through a DNA database.

They got a match to the unsolved case in Washington, D.C., and in 2005, indicted John Doe based on what the Suffolk district attorneys office called his unique genetic profile.

In January 2011, police said they were able to connect Day to the DNA after federal authorities entered his profile into the database after a federal conviction. Day was arrested last week and was ordered at an extradition hearing to turn himself over to Transit Police.

Suffolk District Attorney Daniel Conley applauded authorities for their outstanding work in charging what he called a serial offender. He said when Day returns to court June 27, prosecutors will ask for a confirmation DNA swab to check against the evidence from the womans bag.

The rest is here:
DNA trail leads to MBTA sexual assault suspect