Scott Peterson's lawyer, arguing that Modesto police failed to pursue a "genuine investigation of Laci Peterson's disappearance" last Christmas Eve, is seeking dismissal of double-murder charges against his client.

In a 12-page argument filed with Stanislaus County Superior Court (search) on Monday, attorney Mark Geragos (search) maintains the murder charges against Peterson are groundless, and stated that "police — from the very beginning — decided that their job was to put Scott Peterson on death row."

Geragos will formally move at a Jan. 14 court hearing to dismiss charges that Peterson killed his substitute teacher wife and their unborn son.

Laci Peterson, 27, vanished from her Modesto home last Christmas Eve, and a passer-by discovered her body in San Francisco Bay four months later. Police arrested her 31-year-old husband only days afterward in San Diego.

Stanislaus County prosecutors offered no comment on the motion to dismiss charges.

Geragos' court filing repeated many of his previous objections to the prosecution's case, arguing that there is no physical or circumstantial evidence to link Peterson to his wife's death and no evidence that she and her son died as the result of a crime.

Geragos also charges Modesto Police with ignoring or not following up on leads that pointed to other directions than Scott Peterson.