U.S. courts are weighing in with opinions:

The 10th Circuit’s recent 2-1 decision in U.S. v. Andrus, No. 06-3094 (April 25, 2007), recognized for the first time that a password-protected computer is like a locked suitcase or a padlocked footlocker in a bedroom. The digital locks raise the expectation of privacy by the owner. The majority nonetheless refused to suppress the evidence.

The case was a first for the 10th U.S. Circuit Court of Appeals, and only two other circuits have touched on the issue, the 4th and 6th circuits. The 10th Circuit held that although password-protected computers command a high level of privacy, the legitimacy of a search turns on an officer’s belief that the third party had authority to consent.

Excellent commentary from Jennifer Granick:

The Fourth Amendment generally prohibits warrantless searches of an individual’s home or possessions. There is an exception to the warrant requirement when someone consents to the search. Consent can be given by the person under investigation, or by a third party with control over or mutual access to the property being searched. Because the Fourth Amendment only prohibits “unreasonable searches and seizures,” permission given by a third party who lacks the authority to consent will nevertheless legitimize a warrantless search if the consenter has “apparent authority,” meaning that the police reasonably believed that the person had actual authority to control or use the property.

Under existing case law, only people with a key to a locked closet have apparent authority to consent to a search of that closet. Similarly, only people with the password to a locked computer have apparent authority to consent to a search of that device. In Andrus, the father did not have the password (or know how to use the computer) but the police say they did not have any reason to suspect this because they did not ask and did not turn the computer on. Then, they used forensic software that automatically bypassed any installed password.

The majority held that the police officers not only weren’t obliged to ask whether the father used the computer, they had no obligation to check for a password before performing their forensic search. In dissent, Judge Monroe G. McKay criticized the agents’ intentional blindness to the existence of password protection, when physical or digital locks are such a fundamental part of ascertaining whether a consenting person has actual or apparent authority to permit a police search. “(T)he unconstrained ability of law enforcement to use forensic software such at the EnCase program to bypass password protection without first determining whether such passwords have been enabled … dangerously sidestep(s) the Fourth Amendment.”

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If courts are going to treat computers as containers, and if owners must lock containers in order to keep them private from warrantless searches, then police should be required to look for those locks. Password protected computers and locked containers are an inexact analogy, but if that is how courts are going to do it, then its inappropriate to diminish protections for computers simply because law enforcement chooses to use software that turns a blind eye to owners’ passwords.