Section 638.52.
Cal. Penal Code - PEN § 638.52.
in effect(a)
A peace officer may make an application to a magistrate for an order or an extension of an order authorizing or approving the installation and use of a pen register or a trap and trace device. The application shall be in writing under oath or equivalent affirmation, and shall include the identity of the peace officer making the application and the identity of the law enforcement agency conducting the investigation. The applicant shall certify that the information likely to be obtained is relevant to an ongoing criminal investigation and shall include a statement of the offense to which the information likely to be obtained by the pen register or trap and trace device relates.
(b)
The magistrate shall enter an ex parte order authorizing the installation and use
of a pen register or a trap and trace device if the magistrate finds that the information likely to be obtained by the installation and use of a pen register or a trap and trace device is relevant to an ongoing investigation and that there is probable cause to believe that the pen register or trap and trace device will lead to any of the following:
(1)
Recovery of stolen or embezzled property.
(2)
Property or things used as the means of committing a felony.
(3)
Property or things in the possession of a person with the intent to use them as a means of committing a public offense, or in the possession of another to whom they may have delivered them for the purpose of concealing them or preventing them from being discovered.
(4)
Evidence that tends to show
a felony has been committed, or tends to show that a particular person has committed or is committing a felony.
(5)
Evidence that tends to show that sexual exploitation of a child, in violation of Section 311.3, or possession of matter depicting sexual conduct of a person under 18 years of age, in violation of Section 311.11, has occurred or is occurring.
(6)
The location of a person who is unlawfully restrained or reasonably believed to be a witness in a criminal investigation or for whose arrest there is probable cause.
(7)
Evidence that tends to show a violation of Section 3700.5 of the Labor Code, or tends to show that a particular person has violated Section 3700.5 of the Labor Code.
(8)
Evidence that does any of the following:
(A)
Tends to show that a felony, a misdemeanor violation of the Fish and Game Code, or a misdemeanor violation of the Public Resources Code, has been committed or is being committed.
(B)
Tends to show that a particular person has committed or is committing a felony, a misdemeanor violation of the Fish and Game Code, or a misdemeanor violation of the Public Resources Code.
(C)
Will assist in locating an individual who has committed or is committing a felony, a misdemeanor violation of the Fish and Game Code, or a misdemeanor violation of the Public Resources Code.
(c)
Information acquired solely pursuant to the authority for a pen register or a trap and trace device shall not include any information that may disclose the physical location of the subscriber,
except to the extent that the location may be determined from the telephone number. Upon the request of the person seeking the pen register or trap and trace device, the magistrate may seal portions of the application pursuant to People v. Hobbs (1994) 7 Cal.4th 948, and Sections 1040, 1041, and 1042 of the Evidence Code.
(d)
An order issued pursuant to subdivision (b) shall specify all of the following:
(1)
The identity, if known, of the person to whom is leased or in whose name is listed the telephone line to which the pen register or trap and trace device is to be attached.
(2)
The identity, if known, of the person who is the subject of the criminal investigation.
(3)
The number and, if known, physical location of the telephone line to which the pen
register or trap and trace device is to be attached and, in the case of a trap and trace device, the geographic limits of the trap and trace order.
(4)
A statement of the offense to which the information likely to be obtained by the pen register or trap and trace device relates.
(5)
The order shall direct, if the applicant has requested, the furnishing of information, facilities, and technical assistance necessary to accomplish the installation of the pen register or trap and trace device.
(e)
An order issued under this section shall authorize the installation and use of a pen register or a trap and trace device for a period not to exceed 60 days.
(f)
Extensions of the original order may be granted upon a new application for an order under subdivisions
(a) and (b) if the officer shows that there is a continued probable cause that the information or items sought under this subdivision are likely to be obtained under the extension. The period of an extension shall not exceed 60 days.
(g)
An order or extension order authorizing or approving the installation and use of a pen register or a trap and trace device shall direct that the order be sealed until the order, including any extensions, expires, and that the person owning or leasing the line to which the pen register or trap and trace device is attached not disclose the existence of the pen register or trap and trace device or the existence of the investigation to the listed subscriber or to any other person.
(h)
Upon the presentation of an order, entered under subdivisions (b) or (f), by a peace officer authorized to install and use a pen register, a provider of wire or
electronic communication service, landlord, custodian, or other person shall immediately provide the peace officer all information, facilities, and technical assistance necessary to accomplish the installation of the pen register unobtrusively and with a minimum of interference with the services provided to the party with respect to whom the installation and use is to take place, if the assistance is directed by the order.
(i)
Upon the request of a peace officer authorized to receive the results of a trap and trace device, a provider of a wire or electronic communication service, landlord, custodian, or other person shall immediately install the device on the appropriate line and provide the peace officer all information, facilities, and technical assistance, including installation and operation of the device unobtrusively and with a minimum of interference with the services provided to the party with respect to whom the installation and use is
to take place, if the installation and assistance is directed by the order.
(j)
A provider of a wire or electronic communication service, landlord, custodian, or other person who provides facilities or technical assistance pursuant to this section shall be reasonably compensated by the requesting peace officer’s law enforcement agency for the reasonable expenses incurred in providing the facilities and assistance.
(k)
Unless otherwise ordered by the magistrate, the results of the pen register or trap and trace device shall be provided to the peace officer at reasonable intervals during regular business hours for the duration of the order.
(l)
The magistrate, before issuing the order pursuant to subdivision (b), may examine on oath the person seeking the pen register or the trap and trace device, and any witnesses the
person may produce, and shall take their affidavit or their affidavits in writing, and cause the affidavit or affidavits to be subscribed by the parties making them.
(m)
Notwithstanding any other provision in this section, no magistrate shall enter an ex parte order authorizing the installation and use of a pen register or a trap and trace device for the purpose of investigating or recovering evidence of a prohibited violation, as defined in Section 629.51.
References
referencesCal. Labor Code - LAB § 3700.5.
referencesCal. Evidence Code - EVID § 1040.
referencesCal. Evidence Code - EVID § 1041.
referencesCal. Evidence Code - EVID § 1042.
referencesCal. Penal Code - PEN § 311.3.
referencesCal. Penal Code - PEN § 311.11.
referencesCal. Penal Code - PEN § 629.51.
Source: CA Legislative Counsel Bulk DataURL: https://downloads.leginfo.legislature.ca.gov/pubinfo_2025.zipFetched: 6/27/2026