If a person watches enough TV or reads enough PI novels, they may come away thinking that private investigators can do anything, anywhere, at any time. This is simply not true. Private investigators have rules that they have to obey and disobeying those rules can cost them their license (or worse). Here are some of the things that private investigators cannot do and clients should not ask them to do:
Note: State laws vary; the following are general to most states in the U.S. International laws may vary wildly from country to country.
No U.S. state allows private investigators to represent themselves as the police or other law enforcement officers. This means that they are not allowed to dress in police uniforms or carry badges that suggest that they are local, state, or federal police officers.
Private investigators are not allowed to make arrests other than those arrests that the average citizen can make. Generally, private investigators will leave the arrest part of the operation to the local police as this is almost always the best way to ensure that the offender does not have grounds for dismissal later on in court.
Private investigators are not allowed to tap phones without prior consent. Federal law prohibits both the police and private investigators from tapping phones or even monitoring calls with court approval or consent from at least one of the concerned individuals. Note: In the U.S. 38 states and the District of Columbia require one party give consent. The other 12 states require consent be given by all those involved in the recording. These same rules, more or less, apply to recording conversations not on the phone.
They are not allowed to obtain criminal records and other forms of court documents that are closed to the public. They can, however, check to see if there are court documents and criminal records as long as they use legal methods.
Private investigators are not allowed to go into property illegally. They cannot break and enter, in other words. If they do, they can be charged with a crime just as any other person could be charged for breaking and entering.
Private investigators can run credit checks but they must have consent (in writing) before doing so. A credit report is considered by law to be private information. In addition, private investigators must also have a legal purpose in order to run the credit check.
In all states, private investigators are not allowed to use illegal actions to get information. This might include bribery or threatening a person with physical harm. The simple rule is that private investigators are not allowed to break the law in order to do their jobs. They are considered no different than other citizens in this regard.
It should be noted that information that is gained through illegal methods is often not allowed to be used in court or other legal proceedings. Breaking the laws to get information often results in no gain for the client or the private investigators but rather trouble and frustration.