So says the Supreme Court in State v. Bembry.
The result may not be surprising, given that the US Supreme Court held similarly in 2006's Hudson v. Michigan, and I personally am convinced that the rationale of Hudson (which was adopted by the Court in Bembry) was correct, but I also am sympathetic to those who might view this as a missed opportunity to provide greater protection to Ohio's citizens through new federalism.
The knock-and-announce rule is the requirement that officers executing a search or arrest warrant must knock on the door and announce their identity and purpose before entering. It's a common-law requirement dating back hundreds of years, it's codified in both the United States Code and the Ohio Revised Code, and it's incorporated into the Fourth Amendment. What's not codified in any of those, though, is the remedy for a violation.
In Hudson the Court explained that the purposes of the knock-and-announce rule were to prevent violent encounters that might be expected upon unannounced entry; to preserve the physical integrity of homes; and preserve the privacy and dignity of those inside, who may need a moment to compose themselves. It does not follow that a violation of these rights ought to be remedied by exclusion of evidence. The Bembry Court generally reaches the same conclusions, and even specifically addresses and rejects the call for "new federalism."
Again, this seems right to me. The exclusionary rule does not apply upon every violation of a right associated with freedom from search and seizure, but even if it did, recall that knock-and-announce presupposes a valid warrant. In other words, a neutral and independent magistrate has already determined that the state is permitted to search and seize the evidence or person at issue. Excluding that evidence because officers did not announce their presence prior to entry would be, in an odd way, a punishment that does not fit the crime.