In United States v. Yuknavich, 419 F.3d 1302 (11th Cir. 2005), the defendant whose computer was warrantlessly searched was also a probationer.
The opinion of the 11th Circuit Court of Appeals, 419 F.3d at 1311, made it clear that the key criterion for the Knights balancing test is reasonable suspicion and that the absence of an express search condition is not fatal to the search of the probationer's property:
In sum, assuming the lack of a search condition heightened Yuknavich's expectation of privacy, it did not sway the Knights balancing test such that the probation officers needed more than reasonable suspicion to conduct a search of Yuknavich's computer.
Despite the absence of a state regulation or search condition requiring Yuknavich to submit to warrantless searches, he had a greatly reduced expectation of privacy in his computer. Under the Knights balancing test, the probation officers needed no more than reasonable suspicion of a probation violation to conduct a search of his computer. Because the search was supported by reasonable suspicion, Yuknavich's motion to suppress was properly denied.