The US law on eavesdropping devices differs from state to state in the US and you should understand this before purchasing.

Several federal laws have been enacted by Congress that apply nationwide. According to 18 U.S. Code § 2511(2)(d), at least one party involved in the communication must consent to the interception of the communication. This applies to wire, oral, or any type of electronic communication. Third-party consent is only applicable if one of the parties is an “officer of the United States” (18 U.S. Code § 2511(2)(d)).

Additionally, Congress passed the Electronic Communications Privacy Act of 1986 (ECPA), which updated the Federal Wiretap Act of 1968. The Federal Wiretap Act addressed the interception of conversations over telephone lines but did not cover computer or other digital data interception. This law was further updated by the USA PATRIOT Act to clarify and modernize the ECPA. The ECPA has three titles:

• Title I prohibits attempts or successful interceptions or “procurement of any other person to intercept any wire, oral, or electronic communication.” It also prohibits the storage of any information obtained during phone calls without consent or illegally obtained through wiretapping.

Moreover, the Wiretap Act prohibits unauthorized interception of “wire, oral, or electronic communications” by the government or private individuals. This law also establishes procedures for government officials to obtain warrants to authorize any wiretapping activities. These laws were enacted in response to congressional investigations that revealed numerous instances of government and private wiretapping without consent or legal authorization.

In the United States, electronic surveillance is considered protected under the Constitution and the Fourth Amendment, which guards against unreasonable searches and seizures by the government. The U.S. Supreme Court has also interpreted electronic surveillance as falling under this protection.

 
State Variations

The use of eavesdropping devices is regulated by various legislative bodies in the United States. Laws on the use of eavesdropping devices vary by state. Generally, the differences pertain to whether a state is a one-party consent or two-party consent state. In one-party consent states, only one party needs to consent to the recording, while in two-party consent states, all parties must consent to the recording. In many states, the consent requirements listed below apply only when parties have a reasonable expectation of privacy, such as on private property, and do not apply in public places. (In some cases, protections may extend to conversations in public places.)

States with One-Party Consent: Alabama, Alaska, Arizona, Arkansas, Colorado, District of Columbia (D.C.), Georgia, Hawaii, Idaho, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Minnesota, Mississippi, Missouri, Nebraska, New Jersey, New Mexico, New York, North Carolina, North Dakota, Ohio, Oklahoma, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Utah, Virginia, West Virginia, Wisconsin, Wyoming.

States with All-Party Consent: California, Connecticut, Delaware, Florida, Illinois, Maryland, Massachusetts, Michigan, Montana, Nevada, New Hampshire, Oregon, Pennsylvania, Vermont, Washington.

If you are sure that your principles and laws allow the use of spy bugs, choose and buy.