ST. PAUL — Problems at a St. Paul charter school are adding fuel for critics who say it’s too difficult to figure out who’s accountable when there are problems in Minnesota’s 150 such schools.

Minnesota Public Radio News highlighted troubles at the charter Community School of Excellence in a report Wednesday that pointed to possible gaps in oversight.

An investigation found that the superintendent of the charter school had misused federally subsidized lunch funds and discouraged employees from reporting suspected cases of child abuse.