The tax reform act of 1986 removes the safe-harbor provision for engineers and programmers. This strange sentence means that if a company hires an engineer or programmer - as an independent contractor - and the IRS later decides that this person is really an employee, then the company is liable for back taxes and probably penalties. For other professions, the "safe harbor" provision means that the company is only liable for paying the employer share of taxes going forwards - the previous stuff is handwaved away.
In effect, this scares companies so much that it is very difficult to get hired as a 1099 contractor as a programmer/engineer. The vast majority of companies will require you to be a W-2 employee of some other company (which will be the "staffing agency" or "bodyshop" or "temp agency").
One programmer was driven to fly his aircraft into an IRS building due to this issue.
In effect, this scares companies so much that it is very difficult to get hired as a 1099 contractor as a programmer/engineer. The vast majority of companies will require you to be a W-2 employee of some other company (which will be the "staffing agency" or "bodyshop" or "temp agency").
One programmer was driven to fly his aircraft into an IRS building due to this issue.
https://www.nytimes.com/2010/02/19/us/19crash.html
https://en.wikipedia.org/wiki/2010_Austin_suicide_attack