Can a police person do a reasonable search on a person and find nothing, or is the reasonable-ness of a search predicated on finding something?
Can a search be lawful and just be wrong, or is the search of an innocent person's car inherently unlawful?
For a car search, police people have to have reasonable grounds that a crime has been committed. Can they have that and just be wrong, or is any search that does not find anything incriminating cause for a section 1983 suit?
A search of a suspect can be done according to §102 StPO if there is an assumption that it will lead to evidence. This is a matter of federal law. German law distinguishes between Anfangsverdacht (initial suspicion, required e.g. for searches), hinreichender Tatverdacht (sufficient suspicion, required for the prosecution to initiate a trial), and dringender Tatverdacht (urgent suspicion, required for pre-trial detention). As you can see, searches are on the lowest scale of suspicions. This suspicion has to be based on facts to be legal, but it does not have to be correct to be legal.
A search can also be done to mitigate dangers to the subject of the search, to the police or to bystanders. For instance, someone going into the "drunk tank" would be searched for means of self-harm, and generally anybody being detained by the police would be searched for weapons. This is a matter of state law, and handled differently in the various states. In Berlin, this would be §34 ASOG, section (3).
The reasonableness of a search is not at all affected by what the search happens to reveal or fail to reveal.
Reasonableness is an objective inquiry, based on the circumstances known to the officer at the time of the search. The officer needs reasonable grounds to believe (equivalent to "reasonable grounds" or "probable cause") that relevant evidence will be obtained, or be conducting a search for immediate safety reasons. The search must also be conducted in a reasonable manner.
See generally Canada, Charterpedia: Section 8.
"They found nothing" has never been the basis for finding a breach of Section 8 of the Charter.
Terry v Ohio lays out the rules for stopping and searching. If there is reasonable suspicion for the stop, and the search itself is reasonable, that indeed does bar a 42 USC 1983 suit for the initial stop, because that only allows relief where the police violate clearly established rights.
Terry v Ohio established that a Terry Stop does not violate the 4th amendment; thus, a Terry Stop that comes from the reasonable suspicion of a crime - if by foot or in car - can not be the only reason for a 42 USC 1983 claim.
However, if the suspicion is wrong, that does not remove that there was an initial suspicion. A 42 USC 1983 suit would require police overreach or misconduct, such as extending the stop beyond necessity once the reasonable suspicion is no longer there and nothing was found. Only if during the time the initial suspicion hasn't been removed a new thing brings new suspicions, a further search would be warranted.
The search must be made in order to cement the reasonable suspicion of a crime or for the safety of the officer. The most simple example I can think of:
If they weren’t allowed to not find anything, a search wouldn’t be necessary.
The reasonableness of a search is not based upon the result of the search (which you can’t find out until after the search takes place), but upon having reasonable cause to believe that a search will produce the desired results.
There are no reasonable grounds to search anywhere for anything that would produce a result that anyone now living is guilty of helping murder Julius Caesar.
So reasonable doesn’t mean it’s certain or even possible, rather that it would be reasonable to suppose given the circumstances that something would be found. And in the US at least, that something must be a specific thing. You can’t have a reasonable suspicion that someone is a criminal and a search would find evidence of their crimes, you need to have a suspicion that they did a specific thing.
Suspicion doesn’t require evidence but it requires more than mere hunch, the most common source of suspicion is testimony - someone says they saw or heard something, and that in turn was enough to cause suspicion.
Recently saw a video of a judge dismissing a trespass charge where the police had randomly stopped the accused to ask if he was trespassing and he basically ignored them. If someone had reported him as trespassing that might have been a reasonable stop, but not being expressive in a random stop doesn’t give grounds for suspicion of trespassing. He could have been a serial killer or burglar with every right to be there, or even a totally innocent person that just didn’t want to talk to them.
In the US, this is frequently referred to as reasonable, articulable, suspicion or RAS.
The Supreme Court has said being wrong that the alleged behavior is a crime is insufficient for a 1983 suit, let alone being wrong that a search will produce evidence that someone committed a crime.
If a search was illegal if / because nothing was found, then the police would have extremely strong motivation to find something, anything. So such a rule would be very bad for innocent people.
Searches without warrant are prevented by giving police very strong motivation not to perform them, by making any findings unusable in court even if a warrantless search is performed on a real criminal and finds real evidence against them; again police is motivated not to violate the rights of innocent people.
