The fate of a Boston doctor charged with murdering his wife now rests with a jury of seven men and five women, after lawyers for both sides finished their closing arguments Tuesday afternoon.

Dirk Greineder, 60, sat pensively as he was painted by his lawyer as a troubled, but innocent, man wrongly accused of a heinous crime, and then by the prosecutor as a porn-obsessed murderer who bludgeoned and stabbed his wife of 32 years the morning of Oct. 31, 1999.

"The evidence shows a man guilty of adultery, guilty of infidelity, guilty of using the Internet in … in ways that are disturbing," said defense lawyer Martin Murphy, referring to some of the 473 exhibits and 70 witnesses the jury saw and heard. "But it doesn't say anything about murder."

Prosecutor Richard Grundy urged the jury to use common sense. "The evidence that speaks the loudest," he said, "is that which is the simplest."

Greineder is charged with first-degree murder for the death of his wife, Mabel "May" Greineder, during a regular walk the couple took through the woods of Morse's Pond near their home in Wellesley, Mass. The prosecution alleges Greineder killed his wife to pursue a secret life of Internet pornography and trysts with prostitutes.

The doctor has maintained his innocence, testifying that he separated from his wife in the park after she complained about a sore back and wanted to return home. When he returned, Greineder told the jury, he found his wife dead on the path from numerous wounds.

If found guilty of first-degree murder, he faces life in prison without parole. Judge Paul Chernoff also added a lesser charge, second-degree murder, which carries a sentence of life in prison with a parole opportunity after 15 years.

At the beginning of the trial, Chernoff ruled that the defense would not be allowed to attempt to link this killing to two other slayings that occurred during a six-month period before Mabel Greineder was killed. Still, Murphy was able to allude to a link when he told the jury during his closing arguments that the Wellesley, Mass., police department's case was "focused from the get-go" on his client.

The defense attorney ran through the physical evidence presented by the prosecution in this five-week trial, alleging that it provided only "proof that requires guesswork and conjecture on [the jury's] part."

Murphy reiterated the defense's "transfer" theory that Greineder's DNA could have traveled from a cloth he used to wipe his face to his wife's face and then to the knife. He also attacked the prosecution's repeated assertion that because Greineder's hands were clean after the murder — but his sleeves were bloody — he must have been wearing the gloves that were found with the murder weapon. As Murphy pointed out, Mabel Greineder's blood was found under Dirk Greineder's fingernails.

Murphy pressed the jury to ask themselves what possible motive Greineder, a successful man with a happy family and a soon-to-be-married daughter, would have to kill his wife. And if Greineder was the killer, Murphy asked, why would he have left such a blatant trail of evidence linking him to the murder?

Holding Dirk Greineder's yellow windbreaker, stained with the blood of his slain wife, the lawyer asked the jury, "Can you really conclude that an intelligent man, with a PhD in pharmacology, would choose this way to kill his wife?"

But prosecutor Richard Grundy dismissed this argument as feeble. Greineder's best defense, Grundy cautioned the jury, is that "you don't want to believe that an upstanding physician in an upstanding profession, loved by his children, could commit such a crime."

"If we could gauge pure evil, see pure evil, hear pure evil, it would make all our jobs easier," he continued.

But in his subdued, hour-long statement, the normally aggressive prosecutor appealed to the jury to focus their deliberation on the facts and to use common sense to connect the evidence instead of worrying about a motive.

"Close your eyes and put it upon your mind," he said. "If that image in your head with those facts applied is guilty, then so is the defendant."

Elements of the defense's case, such as the DNA "transfer" theory, said Grundy, are too far-fetched to make sense. An argument that begins with simultaneous nosebleeds is a spurious one, he argued.

Instead, Grundy asked the jury to focus on clear facts, such as Greineder's clean hands, which the prosecution has always said was a sign that the doctor was wearing the gloves found with the murder weapons in a nearby storm drain.

At one point, Grundy held up the blood-drenched T-shirt Mabel Greineder was wearing, placing next to it a photo of Greineder's spotless hands.

"Is that guesswork? Is that speculation? Do you need an expert to come in?" he asked the jury, responding to Murphy's allegation that the prosecution used a "connect-the-dots" approach in its case. "No blood on the defendant's hands. Does that make common sense?"

Grundy closed by attacking the powerful testimony given by Greineder and his three children. He discounted the allergist's three days on the stand, saying the allergist had a "tremendous incentive to testify."

"I'm sure there's general remorse at this time," he said. "I'm sure that the life he had looks really good now."

He also discounted testimony given by each of the three Greineder children. "I would suggest to you that obviously they're clearly biased," he told the jury.

The couple's three children, Kirsten, Colin and Britt, have stood by their father, saying they believe entirely in his innocence. Colin Greineder testified Monday that he knew as early as May 1997 of his father's frequent use of Internet pornography sites.

Colin also testified that he purchased a box of nails the week his mother was killed. His testimony was significant because one of the murder weapons, a two-pound sledgehammer, was purchased three minutes after a receipt found in the Greineder household showed that a box of nails was purchased.

Closing arguments were scheduled to begin Monday but Judge Paul Chernoff received a last-minute fax from Wellesley, Mass., resident Jacqueline Swerling claiming that she and her partner saw a sweaty, dazed jogger the morning that Mable Greineder was murdered.

Swerling, who lives only two miles from the park where the murder occurred, claimed she notified the Wellesley Police Department on November 2, two days after the murder, but never heard back. Police said they never received Swerling's letter.

After testimony from Swerling, her partner Richard Acherson, and Police Chief Terrence Cunningham Monday, the defense decided Tuesday morning not to call either as a witness.

The jury began deliberations after lunch Tuesday.

The trial is being televised by Court TV.