If bugs are illegal why not call the police immediately?
Most patrol officers will not open a case that doesn't have any indication of a crime being committed.
Despite your concerns the responding officer will not be able to determine that you did not put the listening device in place - in fact he may not be able to decide that it is a listening device.
Unless there is immediate danger to persons or property it is better to get a professional to evaluate the situation, produce a technical report and affidavit. This will often be enough evidence for a detective to pursue the case.
Ken Rosenblatt's book High-technology Crime explains clearly how police view these sort of cases. He also covers the corporate view of police.
We often hear the complaint the "the police did not do anything".
Think of the situation from the police perspective.
Most departments are understaffed and have lots of people, politicians and corporations competing for their attention.
Why should they pay attention to an eavesdropping case where the facts are all technical, details are lacking and the person who has the complaint has contaminated the evidence?
Next case, please.