Larger providers temporarily blocked the ISPs that tried to contravene the concerted practice. However, federal statutes and treaties are "supreme" only if they do not contravene the Constitution. Anything deemed likely to contravene the Act is prohibited from DVDs awarded an R18 certificate. The acts include those deemed likely to contravene the Obscene Publications Act 1959. Any laws that contravene the Basic Law are unconstitutional and are of no effect. They are, however, forbidden if they contravene any generally accepted rule. He further ruled that the oath does not contravene either religious or equality rights. These modifications may contravene the law in certain EU states and void insurance ! Georgian Ambassador to Russia Erosi Kitsmarishvili said such unification would contravene international law. The suppression of indigenous languages within the education system appears to contravene this treaty. He has expressed concern that the bill might contravene EU trade law. Thus it is possible to contravene the law as a result of receiving unsolicited images. Contracts which contravene public policy are void. If present, these would contravene the secular basis of the public education system. The result would be that all mandatory sentences would contravene Article 21.