I feel compelled to throw in my proverbial two cents.
I still haven't seen a repost from the original author indicating whether or not he's LE or a corporate investigator. My experience (32 years active law enforcement and 4 years in CF) is completely California based and my comments have to be taken with that caveat.
The very first thing you need to do is, if you are a corporate investigator, is to contact your firm's legal department and seek their advice. If you are LE, you should contact your local prosecutor and seek direction.
In California, if you're investigating child pornography and you're not LE, you might be in a difficult position. In certain circumstances, you might be considered what's known as a mandated reporter. If you, or your firm, ARE a mandated reporter and you fail to notify the local law enforcement agency you would be in violation of state law. This is, in my humble opinion, not a good place to be. Even if you are not a mandated reporter, you also should consider that if you're not LE or a corporate investigator working at the direction of a court order (for what ever reason) you should consider that YOU are in possession of CP. (An even worse place to be.)
On the law enforcement side (again, California rules), and you are conducting the investigation under the auspices of a search warrant, the warrant will specify what you can search and what you can search for. If the warrant is properly written (from a procedural standpoint, not a legal standpoint) they can generally be written in broad enough terms that they cover contingencies, but still be constitutionally sound. (You don't have to specify a particular make and model of computer, for example; "electronic storage media" should be specific enough).
Based on the terms of the warrant, if the evidence of fiscal fraud doesn't come within the scope of the original search warrant, you need to get a second warrant. This type of warrant is usually referred to as a "piggy back warrant". As with all search warrants, the request for the warrant is made in the form of an affidavit. For a piggy back warrant, you don't need to re-invent the wheel in terms of probably cause. You start with "Judge X issued a search warrant, the affidavit for which is attached. Based on that warrant I conducted a forensic examination. During that examination, I found the following evidence of fraud (in general terms). I therefore request an additional warrant for evidence of that crime."
Again, laws are different depending on your country, your state, or even your local jurisdiction. Check with your local legal authority.
Sorry if I'm long winded or whipping a dead horse. That's why I don't post very often.
Still, I would not proceed with ANY discovery of suspected CP without consulting a lawyer.
And the OP was about the "reverse effect"
finding "non CP", but rather other elements that may constitute evidence of a when investigating fro CP and after having found CP already.
At least here in Italy, CP is seen as being a "particularly repugnant " kind of crime, for which "special" investigating rules and Laws have been made.
The same doesn't happen for a "common" credit card fraud.
So, I believe, that the case of CP discovered "by accident" while carrying another investigation would have different management by the LE than the case of probable evidence of "another crime" found while doing CP oriented investigations.
jaclaz
Lets say it happened the opposite way. You were investigating Fraud and you ran across Child Pornography. First you have to justify why you were looking at images when investigating a fraud case (Fake ID's, Scanned Documents, etc.)
Then of course you would get a warrant or additional permission to retrieve the cp.
Hope this helps. Seems to make more sense if you look at it that way in my opinion.
That isn't a slight by any means, it's just that a lawyer will have a better idea of the shape of the law in your area than yourself or people on some web forums.
Good. )
Now that it's clear that any advice given "generally" and "on a board" is pretty much pointless when it comes to delicate matters such as the rights of an individual and the lawful gathering of evidence against him/her, can we play a bit? ?
Not useless, just practical. Given the varied nature of plain view in regards to digital/computer forensics it would be unwise for anyone to advise the original poster to shift the investigation towards a credit card fraud case. From my studies, depending on the law of the land in his area, he might be within his right to investigate the credit card fraud. In other cases, investigating the credit card fraud without a warrant may harm the case substantially.
Your examples of searching a house are accurate, but the courts have not, as yet, decided plain view in regards to computers. Once you start to examine a computer, is everything inside considered plain view, or not? The courts are divided on this, and the Supreme Court has not yet taken up a case.
However, using your example number 1. The police would have evidence of child pornography, yes. But they would not be allowed to search the house for more child pornography. They would still only be able to search the house for large LCD tv's, and the places they could reasonably be. The other two examples maybe thrown out of court, because a LCD tv could not reasonably be inside a penthouse or an accounting magazine.
I'd imagine that in the future, the courts will follow the established plain view doctrine, but until then the question of if you need a warrant to continue or not will reside with the prosecutor.
The above assumes the original poster was in law enforcement.