Migu or miggo (translation: "since") (Hebrew: מיגו) is a Talmudic law concept relating to civil law disputes. A migu is a reason that a claim that would otherwise be rejected by a Jewish civil court should be accepted based on the fact that the litigant could have prevailed in the case based on a different claim were he disposed to lie. To be effective, the logic underlying the migu must be impeccable and there are a variety of cases in which the Migu argument is invalid.
One classic example of where a Migu does work is in the area of a loan repayment dispute. Where the lender accuses an alleged borrower of defaulting on an oral loan made without witnesses, the borrower may prevail in the case by claiming that the loan did occur, but that it had already been repaid. Normally, when one makes a claim that a loan has been repaid, he would be expected to produce evidence that it had been repaid, such as a receipt. However, in this scenario the borrower would prevail under the theory that he must be telling the truth, as if he were interested in lying to the court, he could have simply said that the loan never happened. Since the lender cannot prove the existence of the loan, that claim would have prevailed. Therefore, the claim that the loan was repaid is believed as well. This is a classic Migu.