Psychological studies, such as the one Stanley Milgram carried out at Yale University and published in 1974, have repeatedly shown that, given certain conditions, 80% of most populations will either collude or directly take part in acts of violence.

ECONOMIST: Civilians in war

It would be unseemly for law firms to collude on their billable rates in an antitrust case.

FORBES: How Many Law Firms Does It Take To Sue An Egg Company? 34, Apparently

In what other industry can the biggest suppliers collude and fix prices with impunity?

FORBES: Bumbling Bernanke Bamboozled By Broken Bounce-back

In other words, money managers and brokers may collude to the detriment of retail investors.

FORBES: The Growing Scrutiny of Pensions ( August 22, 2005)

Companies may collude to fix prices internationally, or agree not to compete in each other's markets.

ECONOMIST: The marriage of trade and trustbusting

Russian organized crime syndicates and criminally linked oligarchs may attempt to collude with state or state-allied actors to undermine competition in strategic markets like natural gas, oil, aluminum, and precious metals, the National Security Council attests.

FORBES: Russian Organized Crime Strategic Threat to US - NSC

In effect, anti-dumping measures encourage domestic and foreign producers to collude to raise prices.

ECONOMIST: Unfair protection

Its the latest trick in the 'dumbing-down' of exams in which everybody who matters (exam boards , headmasters , ministers) collude.

BBC: Extra marks for exam day 'stress'

First, it underlines that, with a more open system in the Commons, it is no longer possible for governments and Oppositions to collude to prevent prime-time debates on euro-issues.

BBC: Backbench muscle

According to a source who is an expert in internal audit services to public companies, internal controls are not very effective when executives collude and conceal information.

FORBES: A Tale of Two Lawsuits -- PricewaterhouseCoopers and Colonial Bank