Trespess ab initio applies to civil tort law and cannot sustain the exclusion of evidence in a criminal setting. On Lee v. United States, 343 U.S. 747, 752 (1952); see also McGuire v. United States, 273 U.S. 95 (1926). There’s plenty of other cites: Hoffa v. United States, 385 U.S. 293 (1966); Lewis v. United States, 385 U.S. 206 (1966); United States v. White, 401 U.S. 745 (1971); etc.
Now, if your client had already been indicted on drug trafficking and retained you as an attorney, you might be able to raise a sixth amendment defense. Massiah v. United States, 377 U.S. 201 (1964); United States v. Henry, 447 U.S. 264 (1980).
You might have better luck with a standard entrapment defense…
Also, I don’t see why this would change in light of Jardines. The use of a trained narcotics detection dog to sustain probable cause is analogous to the use of a radio tranceiver to sustain probable cause. If Jardines had invited the dog into the house, he would be waiving his Fourth Amendment rights, even if unaware of the dog’s nature. Likewise, if your client invited an informer into his house, the government may use evidence gathered from a radio tranceiver on said informer.
You would think that among the thousands of lawyers employed by organized crime throughout the decades, one would have used this defense if it was in any conceivable way valid.
That is, the idea is not that there is a (revocable) implied license for police officers to approach our homes. But that there is (in some abstract sense) an implied license for “the public” (whether girl scouts or mailmen or vacuum salespeople) to walk up to our door and knock. And, we say, it’s not a “search” for Fourth Amendment purposes when the police do that which the public may do.
It isn’t really a question of trespass (presumably if you have a sign that says “no police, girls scouts, or roofers,” then you’ve removed a subset of the public from the general license), it’s a question of Fourth Amendment protections and what we’re willing to tolerate from government agents.
To me, Jardines is an extension of the cases that recognize, for example, that you can’t walk up to the front door after running around the the backyard first or that you can’t look under tarps, etc., on your way there. It’s not that the police cannot do it, so much as the general “public license” (that we allow the police to take advantage of) doesn’t extend to those actions – no girl scouts in the backyard. Apparently a dog falls within that rule.
To be sure, there is some weird language in Jardines (for example: “that depends upon whether the officers had an implied license to enter the porch, which in turn depends upon the purpose for which they entered”). I would read that in light of the scope of the public license (“the background social norms that invite a visitor to the front door do not invite him there to conduct a search”) rather than the idea that you can limit the license to omit law enforcement obligations. (Footnote 4 seems to say that as well).
How’s this? The owner excludes or welcomes people, not characteristics. Thinking about the sign cases, if the owner of a house had a big scary sign that said No Trespassers, but when the police showed up he said ‘C,mon in, fellas’, the sign would be of no consequence - he would have waived its effect.
There is no doubt that your client actually allowed snitch on client’s premises at all relevant times. Let us accept that there can be no such thing as ex post facto trespass/refusal of entry. I welcome my son-in-law into my home on Saturday, but when I find out on Monday he is cheating on my daughter, I purport to revoke his welcome on Saturday, and try to prosecute him for trespass. Obviously, such a claim will fail. If we accept that there is no such thing as ex post facto refusal of permission to enter, then the test for who does not have permission must be determinable 1) at the time of entry, 2)by the property owner. Your error is in thinking that because the snitch knew of his characteristic, that triggers a exclusion. But it can’t if the owner did not know about it, and actually welcomed him in.
Shortly put, you can’t set up a rule for exclusion on the part of the owner that can only be actioned by the owner after the event. It’s not a valid ‘rule’, because the person who needs to action it, at the time he needs to do so (the time of entry) can’t. Such a ‘rule’ is not bad for vagueness, as others have accepted, but bad for indeterminability. Such a rule would be impossibly contradictory. I could purport to happily welcome someone into my home (indeed, actually welcome them), and simultaneously refuse them entry. Since permission to enter must come from the owner, then the owner must decide at the time of entry whether someone is welcome. Any other rule is impossible of operation.
The case is quite different from the sign cases, like Sullivan. They do not deal with the situation you are positing, that is the simultaneous approval/disapproval of entry you are trying to conjure here.