They are scams dependent on regular government bailouts!-----Federal bailout gives $635 million to carpenters union pension plan - Michigan Capitol Confidential

There’s nothing in place to prevent a repeat - Jamie A. Hope 

The federal government is spending $635 million in taxpayer funds to bail out a multiemployer pension fund for a Detroit carpenters union. Pension experts warn that the bailout comes with little or no accountability and no indication that it won’t happen again...
A multiemployer pension system is funded by more than one private employer. It usually benefits trade union employees. 

• Currently, 94% of multiemployer pension participants are in plans that are less than 60% funded, according to Greszler.
• This unconditional bailout of a select number of private union pension plans is especially bad, Greszler added, because it doesn’t require plan administrators to fix the problems that led to underfunding...
• One of the major problems with multiemployer pensions is that, unlike single-employer pensions, there are no laws or rules against underfunding and making false promises, Greszler said...