What is the test for a search and seizure in civil cases?

'When, * * * the very purpose of an illegal search and seizure is to get evidence to introduce at a trial, the success of the lawless venture depends entirely on the court's lending its aid by allowing the evidence to be introduced. * * *. Out of regard for its own dignity as an agency of justice and custodian of liberty the court should not have a hand in such 'dirty business'. [Citation.]' (People v. Cahan, supra, 44 Cal.2d at p. 445, 282 P.2d at p. 912.)