on the fiddle
US /ɑn ðə ˈfɪdl/
UK /ɑn ðə ˈfɪdl/

1.
做手腳, 搞欺詐
involved in dishonest or illegal activities, especially involving money
:
•
He was caught on the fiddle, taking money from the company.
他因從公司拿錢而被抓到做手腳。
•
Many politicians are suspected of being on the fiddle.
許多政客被懷疑做手腳。