Firms that donate to political parties twice as likely to win government contracts, analysis finds

Transparency group says donating companies should be banned from government contracts but constitutional expert disagrees

• Follow our Australia news live blog for latest updates
• Get our morning and afternoon news emails, free app or daily news podcast

Companies that make political donations are more than twice as likely to win government contracts and should be banned from working with departments for an entire electoral cycle, according to a key transparency group.

But a constitutional expert has warned a ban could be an overreaction that confuses coincidence with corruption, given public servants who award contracts may have no idea of recent donations to political parties.

Sign up for Guardian Australia's free morning and afternoon email newsletters for your daily news roundup