A Fairfax County judge ruled yesterday that there was insufficient evidence to present to a grand jury the case against a Springfield baby sitter charged with criminal neglect of a 10-month-old girl who died of an overdose of a drug that sometimes is used to treat bed-wetting.

The decision by Juvenile Court Judge Michael J. Valentine left standing the charge against day care provider Martha E. Guba concerning Ashley Snead, who died in Guba's home on July 28.

But it is now up to the commonwealth's attorney's office to decide whether to go to the grand jury for an indictment that would result in a trial. Robert F. Horan Jr., the chief prosecutor, said he had not made that decision and noted that the "overwhelming percentage" of felony cases that are prosecuted are sent to the grand jury by judges.

It was unclear at yesterday's hearing how or where the child ingested the drug, imipramine, which is used to treat depression in adults and is sometimes given to children older than 6 with a bed-wetting problem.

Valentine said, "It's a horrible thing, a child has died," but added, "the testimony was not sufficient" and did not "establish that {Guba} withheld treatment in such a way that resulted in the death of the child."

In charging Guba with "willful and knowing neglect," county police did not say that she had administered the drug to the child, but rather that Ashley ingested it while in Guba's care. They also said Guba had waited several hours after noticing the child was lethargic before calling for help.

The prosecution contended that Guba first told police she knew nothing about the drug, but that later she speculated that it was her husband's and that it might have been put in trash where Ashley might have found it.

Guba did not testify. Her attorney, Thomas J. Morris Sr., described her as a "caring, loving person" who had not knowingly neglected the child. The prosecution "would be foolish to proceed," he said.

Jane Snead, Ashley's mother, testified that Guba had called her at work and told her the child had eaten a Tylenol pill from a quantity that had spilled from a bottle but was going to be fine. Later, Snead testified, Guba called back and said: "Get here fast, fast! Ashley's dying! Ashley's dying!"

The autopsy determined that the child had ingested the equivalent of 11 to 33 imipramine tablets, enough to kill an adult.

Morris argued that there was no way to determine when the drug was consumed and asked Snead if she had suspected neglect during the eight months that Guba had been Ashley's sitter.

"I was not aware of any abuse," Snead replied tearfully.

After the judge's ruling, Guba wept and told a reporter: "I did nothing . . . . I loved all of my kids I looked after. And I took good care of them. I don't have one single person who wouldn't bring their baby back tomorrow."

Snead also cried after the ruling. She and her husband referred reporters' questions to their attorney, who had no comment.