After successfully getting the Chicago Police Department to hand over records showing that it purchased cell site simulator devices, also known as IMSI catchers or stingrays, one local activist has now filed a second lawsuit in an attempt to better understand precisely how the stingrays are actually used.

The new lawsuit was filed on Tuesday by Freddy Martinez, a 27-year-old Chicagoan who works in the software industry.

Martinez’ earlier lawsuit resulted in three pages of invoices, dated 2009, showing that the department purchased an AmberJack upgrade (a model of stingray) and a StingRay II upgrade. While "StingRay" is a trademarked name and particular product of the Harris Corporation, it has entered the technical lexicon as a generic term, like Kleenex or Xerox.

As a result of the CPD’s disclosure of these documents, the agency has now filed for a motion to dismiss in the first lawsuit, and the two sides are set to meet in a Chicago court room on Wednesday. Martinez and his attorney will continue to press for more documents to be released.

The new suit specifically asks for, among other records:

All court orders for any instances in which Chicago Police deployed IMSI Catchers

All formal or informal policies, procedures, orders, directives, or other such records that pertain to when, why, where, how, and by whom IMSI Catchers may be deployed

All records discussing the constitutionality of deploying IMSI Catchers

"The public has a right to know the extent to which the police are secretly taking information from their cell phones and whether their Constitutional rights are being protected in the process," Matt Topic, Martinez’ lawyer, said in a statement. "The Chicago Police Department has refused to produce a single document that would show the extent this is happening and with what Constitutional safeguards. This plainly violates the Freedom of Information Act and raises serious Constitutional concerns."

No comment

Relatively little is known about how stingrays are precisely used by law enforcement agencies nationwide, although documents have surfaced showing how they have been purchased and used in some limited instances.

Last year, Ars reported on leaked documents showing the existence of a body-worn stingray. In 2010, Kristin Paget famously demonstrated a homemade device built for just $1,500. Cops have lied to courts about the use of such technology. Not only can stingrays be used to determine a phone’s location, but they can also intercept calls and text messages.

In recent months, some new information has trickled out as the result of public records lawsuits in various jurisdictions—particularly Florida. Late last month, new documents released by the City of Oakland, California, revealed that it is one of a handful of American jurisdictions attempting to upgrade an existing cellular surveillance system.

Harris Corporation, makers of the StingRay and other related devices, has traditionally refused to speak with Ars about its products. "We do not comment on solutions we may or may not provide to classified Department of Defense or law enforcement agencies," Jim Burke, a spokesman for Harris, previously said.