McClatchy DC: Here’s another politician who paid family for campaign work
The legal issue is that you cannot use campaign funds for personal use, so you can't just give your mother-in-law $500 a month, that's illegal.
FEC rules give congressional candidates wide leeway in spending their campaign funds. Candidates are allowed to hire their spouses or other relatives as long as they pay them at a fair market rate.
“The question is if she’s actually doing $500 a month’s worth of services for it, and would he pay someone else the same amount to do the same thing,” said Larry Noble, general counsel of the nonpartisan Campaign Legal Center in Washington, which works on campaign finance issues. Mulvaney told McClatchy the work Lynch was paid to do was “redistributed among others in the organization” when she passed away.
When it comes to vague descriptions like “consulting,” it may be hard to determine whether the amount paid was fair, Noble said. However paying family members for campaign work is a “relatively common practice and candidates often say they trust their family,” he said, "it's a relatively common practice, so you do see it. But ican raise questions."
“So you do see it, but whenever (members of Congress) do this, even if it’s not a lot of money, it can raise eyebrows,” he said. “Especially if the job is somewhat amorphous.”