Government surveillance of private citizens has increased dramatically since the tragic events of September 11, 2001. One of the laws that resulted from the terrorist attacks on that date was the Patriot Act, formally known as the Uniting and Strengthening America by Providing Appropriate Tools Required to Intercept and Obstruct Terrorism Act. The balance between security and privacy has tilted toward security since the enactment of this law, which allows the government to gain access to many types of information about private citizens.
Some problems have arisen in implementing the Patriot Act, through which law enforcement can discover evidence related to criminal but non-terrorist activities. Before the Patriot Act, rules prevented law enforcement and related government agencies from dodging constitutional restrictions on the ways in which they could collect evidence. The concern was that law enforcement would be able to get an intelligence surveillance warrant by meeting the much lower standard for that type of warrant, and they could use that warrant to detect ordinary criminal activity. This could infringe on individual rights if the situation would not meet the probable cause standard required to get a criminal warrant.
Changes to Surveillance
Following the Patriot Act, law enforcement can get a warrant for both intelligence purposes and criminal investigation purposes. As long as gathering evidence for an investigation is a significant purpose of the warrant, it does not need to be the only purpose of the warrant. Thus, law enforcement can use the lower standard for intelligence warrants to open the door to searches that previously would have required a criminal warrant. Getting an intelligence warrant still requires showing that the subject of the search or surveillance should be a subject of investigation. The courts that issue these warrants tend to give the government a substantial benefit of the doubt, though.
In the post-9/11 era, intelligence agencies have the authority to collect metadata from service providers, which can contain the email addresses, phone numbers, and call histories of individuals. The government has an especially free rein in monitoring electronic (internet and telephone) communications of citizens, compared to other activities.
Effect on Ordinary Criminal Defendants
As a result, people who are involved in a crime that has no national security implications may be caught because of evidence obtained through Patriot Act surveillance. (There would need to be some initial information that triggered a suspicion of terrorist activity, but this could be relatively minor.) The Patriot Act may even justify home searches by the FBI based on a mild suspicion that an individual is connected to terrorism. An FBI agent must provide notice but does not need a warrant for these searches. The FBI may conduct a search without warning while the resident of the home is absent, as long as an agent leaves a note that they were in the home. Any evidence in plain view during a search for terrorism-related evidence may be transferred to local law enforcement to explore criminal charges. The Patriot Act may even affect the way in which a criminal defense attorney represents a client, so you should consult a lawyer if you are involved in an investigation based on the Act.