Durkan was spoken of as a candidate last year to head the US legal department that has caused the biggest crisis to hit football`s scandal-tainted world body.
“Quinn Emanuel (QE) are representing FIFA and Jenny Durkan is part of the QE team,” a FIFA spokeswoman told AFP.
US authorities last month indicated 14 people, including nine top football officials and five sports business executives over tens of millions of dollars of bribes for media rights contracts.
Swiss authorities are also investigating the award of the 2018 World Cup to Russia and the 2022 tournament to Qatar.
Loretta Lynch who was named US Attorney General in place of Eric Holder said that corruption was “rampant” at FIFA.
The storm played a key role in the announcement of FIFA president Sepp Blatter this month that he would step down.
Durkan, the first openly gay top prosecution official in the US system, was the US attorney for the western district of Washington state until September last year.
In five years in the post the 57-year-old handled major civil rights cases involving Seattle police and cyber crime.
She also handled the terrorist case against an American Muslim, Abu Khalid Abdul Latif, who was found guilty of planning a 2011 attack against a military base near Seattle and Ahmed Ressame, an Algerian accused of plotting an attack on Los Angeles airport on the eve of the 2000 millennium.
Since January Durkan has been a partner in the Los Angeles based Quinn Emanuel Urquhart and Sullivan which has about 700 lawyers around the world and specialises in international affairs.