Although the first investigation into the theft of development funds last year named only five former lawmakers, the anticorruption commission’s former leader, Mr. Jiménez, said that as many as 60 current and former legislators could be involved, including the powerful head of Congress, Mauricio Oliva.A review of the social development funds at the center of the first case shows just how casually government money was allocated — and why lawmakers may have been in such a hurry to shut it down.Beginning in 2006, lawmakers set aside $20 million annually to spend on projects in their districts. Half of that money was spent at the discretion of the head of Congress, Mr. Hernández’s position from 2010 to 2014, according to an analysis of the program by Democracy Without Borders. Congress did not provide details of the spending that Mr. Hernández directed during those years.The money goes to nonprofit organizations, some linked to the lawmakers themselves. Investigators with the National Anticorruption Council say that in many cases, projects were only partly completed, or not at all. Some nonprofits presented photographs of the same completed project as evidence that they had finished their work.Over two days in 2015, five lawmakers wrote directly to Mr. Hernández — who was by then the president — to solicit donations, and two days later his office ordered the money disbursed, all to the same nonprofit organization, documents showed.That organization was recently denounced by the National Anticorruption Council for fraud.In one example of the ties between lawmakers and the nonprofits, Renan Inestroza, a National Party deputy, is linked to a network of such organizations that has received at least $3.8 million in government funds.Mr. Hernández has also steered much of his presidency’s signature social program, Vida Mejor, which means Better Life, to these nonprofit groups, including one organization where his sister, Hilda Hernández, served on the executive board. Ms. Hernández died in a helicopter crash in December.