The Media for Democracy Club has called on the House committee on laws, justice and human rights to investigate alleged improper links between the Democrat Party and the Blue Sky satellite TV channel.
The group, led by Jutipong Poommul, yesterday handed a petition asking for the probe to Pracha Prasopdee, the vice-chairman of the committee and the Pheu Thai MP for Samut Prakan.
Mr Jutipong said Democrat involvement with the Blue Sky channel could be in violation of Section 48 of the constitution.
The section prohibits MPs and elected senators from holding any shares in a media organisation.
If the Democrat Party or any Democrat MPs were found to have violated Section 48, the party could be dissolved, he said.
The group also submitted VCD recordings of the Sai Lor Fah (Lightning Rod) talk-show programme to Mr Pracha to back up their claims.
The show is moderated by three Democrat MPs_Sirichok Sopha, Thepthai Senpong, and Chavanond Intarakomalyasut.
The programme caused a storm last month when the trio commented on Prime Minister Yingluck Shinawatra's controversial visit to the Four Seasons Hotel by using suggestive statements regarded by many viewers as inappropriate.
Mr Jutipong added that Mr Sirichok once said in one broadcast that "the Thaicom company can't turn off my satellite TV signal, I have paid the bill."
The word "my" implies that Mr Sirichok is involved in the management of the Blue Sky channel, Mr Jutipong said.
Mr Thepthai yesterday denied the group's accusation, saying the party had nothing to do with the Blue Sky satellite channel and did not violate Section 48 of the constitution.
As for his part in the Sai Lor Fah talk-show, Mr Thepthai said it was normal for politicians to appear on television to express their opinions.
Supatcharee Thammaphet, a Democrat MP for Phatthalung, expressed concern that if the House committee agrees to take up Mr Jutipong's petition, it could be seen as attempting to intimidate media organisations.
"It seems the craze for media interference has returned," Mrs Supatcharee said.