How do insurers check no claims bonus?

How insurers check no claims bonus in Australia and UK is via insurance reference databases, previous insurer proof, and self-declaration with verification at claim, with insurers checking Insurance Reference Services in Australia and Claims and Underwriting Exchange CUE in UK, plus asking for renewal notice showing no claims bonus years and claims history. In Australia, insurers check no claims bonus via Insurance Reference Services IRS database, which records claims history and no claims bonus years reported by insurers, plus they ask for proof of no claims bonus via renewal notice from previous insurer showing no claims bonus years 1 to 6+ years and claims in last 5 years, with self-declaration at quote 1 to 6 years no claims and 0 claims, verified at claim time by contacting previous insurer and checking IRS. For example, you declare 5 years no claims 50% discount at quote with Budget Direct $1,000 base premium = $500 premium, Budget Direct checks renewal notice from NRMA showing 5 years no claims and no claims in 5 years, plus checks IRS database no claims reported, and if you had at-fault claim $5K 1 year ago not declared, IRS shows claim and insurer voids discount and may void policy with claim denied $10K to $50K for non-disclosure. In UK, insurers check via CUE database Claims and Underwriting Exchange, which records all claims $1K to $50K in last 5 years, plus ask for proof of no claims bonus certificate from previous insurer showing years and claims, with self-declaration at quote. So insurers check no claims bonus via IRS database in Australia and CUE in UK, plus renewal notice proof from previous insurer showing years and claims, with self-declaration verified at claim, with false declaration considered fraud with policy void and claim denied $10K to $50K.