Cooking dinner and picking up the dry cleaning recently netted Texas Rep. Stephen Frost, D-Atlanta, a $100 fine.

The household chores were part of an investigation in June when Frost was fined by the Texas Ethics Commission for converting political contributions to personal use for purchases like groceries, cleaning supplies and dry cleaning.

“Stephen thought if it was proper for him to buy food at a restaurant during session, he could buy it for his apartment,” said Frost’s political adviser, Jeff Crosby. “That wasn’t the case.”

After Frost reported his exp...