Shortly after Paul Hartley had given the visitors the lead on 51 minutes with a deflected shot from inside the box, Richmond waved play on when United striker Roy O’Donovan appeared to be tripped by defender Gary Caldwell inside the box.
Richmond then injured himself running into Celtic midfielder Shunsuke Nakamura and had to be replaced by fourth official Iain Brines – before substitute Francisco Sandaza nipped in at the near post to flick a Craig Conway cross past Bhoys goalkeeper Artur Boruc and secure a draw in this Clydesdale Bank Premier League match.
Levein was fined a record £5,000 (€6,300) last week for castigating referee Mike McCurry for a catalogue of errors during a 3-1 defeat at Rangers in May.
Alluding to that game, the United boss went easy on Richmond – who had been taken to hospital.
He said: “I haven’t seen it, but everybody tells me it was a stonewall penalty. I thought he was looking right at it. But I don’t know. I like Charlie and I think he’s a decent referee.
“At least it was only one mistake inside the penalty box today, and I’ve got to put that down as an error – because the alternative isn’t worth thinking about. If I can’t speak my mind and represent my football club and come out after a game where we’ve had five blatant decisions go against us, then I shouldn’t be doing my job.
“I will continue to speak out when I feel we’ve been treated in an unfair manner.”
Unsurprisingly Celtic manager Gordon Strachan had a different view of the penalty incident.
He said: “I didn’t think it was a penalty – because I was convinced he was going to give a free-kick before it for number 10 (O’Donovan), not for the first time, not even looking at the ball and jumping in to ‘Mick’ (Stephen McManus).
Strachan said his side paid for profligacy in front of goal, especially in the case of last season’s top scorer Scott McDonald – who missed a late sitter.
He said: “We played better than last week (against St Mirren) and looked livelier. We had the opportunity to finish the game and couldn’t take it, so we have nobody to blame apart from ourselves.
But the players can be pleased with some good performances at times. It could be a big point, come the end of the season.”
O’Donovan tried not to put too much emphasis on the penalty incident, saying: “It could have been a penalty – and I thought it was a penalty. But then again, I’m biased.
“He didn’t give it; we can’t argue too much, and a draw was a fair result.”
DUNDEE UTD: Zaluska, Kovacevic, Kenneth, Wilkie, Grainger, Flood (Conway 78), Scott Robertson, Gomis, David Robertson (Buaben 64), Feeney (Sandaza 64), O’Donovan.
CELTIC: Boruc, Hinkel, McManus, Caldwell, Wilson, Nakamura (Robson 68), Hartley, Scott Brown, McGeady, McDonald (Samaras 88), Vennegoor of Hesselink.
Referee: C Richmond.