3. The ratcheting effect

Once immunity is offered, it can be hard to convince an embattled leader that the offer will expire unless immediately accepted. In their working paper, Bennett, Hagh and Ritter argue that leaders are likely to pocket the offer and stall for time while they try to wear down the opposition. Manuel Noriega, for example, prolonged his term in power through two different U.S. golden parachute offers, until negotiations finally failed and the U.S. intervened by force.

The U.S. can use economic sanctions, however, to convince Maduro that time is not on his side.