Establishing probable cause. A warrant, of course, requires probable cause. In general, probable cause to search a digital device is no different from probable cause to search a physical object or location. But there are a few probable cause issues that are unique to digital searches.
Probable cause may be based on an IP address. Investigators sometimes determine that criminal activity has been conducted through a particular Internet Protocol address, or IP address, and are able to trace the IP address to a residence, only to learn that the residence has an unsecured wireless network. In such a case, investigators may be unable to rule out the possibility that a neighbor or a passer-by, rather than a resident, used the network for criminal purposes. Nonetheless, courts have generally ruled that there is probable cause to search the digital devices at the residence, as residents are the most likely users of the network.
Probable cause in child pornography cases. Courts have addressed a number of recurrent issues that arise in child pornography investigations. In general:
• When probable cause is based on a witness having seen child pornography on a suspect’s digital device, the officer who applies for the search warrant should provide an explicit and detailed description of the images or videos seen by the witness. If the officer simply describes the material as “child pornography,” a judicial official may be unable to make an independent determination about the nature of the material and the existence of probable cause.
• When probable cause is based on information that a suspect had child pornography on his digital device's weeks or months in the past, an officer with experience in child pornography investigations should explain in the search warrant application that individuals who view child pornography tend to retain it. When presented with such information, courts often recognize that information that a suspect has child pornography on his or her digital devices does not easily become too outdated, or “stale,” to support a search warrant.
• Where there is evidence that a suspect has had sexual contact with children or has visited non pornographic web sites oriented towards pedophiles, these facts may help to support a finding of probable cause to believe that child pornography will be present on the suspect’s digital devices. However, these facts alone may not be sufficient to provide probable cause.
Probable cause may be based on an IP address. Investigators sometimes determine that criminal activity has been conducted through a particular Internet Protocol address, or IP address, and are able to trace the IP address to a residence, only to learn that the residence has an unsecured wireless network. In such a case, investigators may be unable to rule out the possibility that a neighbor or a passer-by, rather than a resident, used the network for criminal purposes. Nonetheless, courts have generally ruled that there is probable cause to search the digital devices at the residence, as residents are the most likely users of the network.
Probable cause in child pornography cases. Courts have addressed a number of recurrent issues that arise in child pornography investigations. In general:
• When probable cause is based on a witness having seen child pornography on a suspect’s digital device, the officer who applies for the search warrant should provide an explicit and detailed description of the images or videos seen by the witness. If the officer simply describes the material as “child pornography,” a judicial official may be unable to make an independent determination about the nature of the material and the existence of probable cause.
• When probable cause is based on information that a suspect had child pornography on his digital device's weeks or months in the past, an officer with experience in child pornography investigations should explain in the search warrant application that individuals who view child pornography tend to retain it. When presented with such information, courts often recognize that information that a suspect has child pornography on his or her digital devices does not easily become too outdated, or “stale,” to support a search warrant.
• Where there is evidence that a suspect has had sexual contact with children or has visited non pornographic web sites oriented towards pedophiles, these facts may help to support a finding of probable cause to believe that child pornography will be present on the suspect’s digital devices. However, these facts alone may not be sufficient to provide probable cause.