An MP who is launching an inquiry into excessive and possibly unlawful court secrecy says a new type of gagging order is hampering the work of investigative journalists.

John Hemming said the new breed of injunction, which was used in relation to a case in the high court in London last week, meant journalists could face jail simply for asking questions.

"This goes a step further than preventing people speaking out against injustice," said Hemming, the Liberal Democrat MP for Birmingham Yardley and a longtime campaigner against secrecy. "It has the effect of preventing journalists from speaking to people subject to this injunction without a risk of the journalist going to jail. That is a recipe for hiding miscarriages of justice."

Hemming has labelled the new gagging order the "quaero injunction" after the Latin word "to seek".

"It puts any investigative journalist at risk if they ask any questions of a victim of a potential miscarriage of justice … I don't think this should be allowed in English courts."

There has been growing concern over the use of gagging orders in UK courts. It is not known precisely how many superinjunctions have been issued, but an informed legal estimate is that as many as 20 have been granted in the UK over the last 18 months.

In the most notorious case, the oil trader Trafigura last year briefly obtained a superinjunction against the Guardian to suppress a leaked report on its toxic waste dumping, which even prevented reporting proceedings in parliament.

Earlier this month, Hemming highlighted a new type of hyperinjunction which forbids the recipient talking to their MP.

He says he is now launching an inquiry in parliament into excess court secrecy and is planning to collect a range of gagging orders that he will then analyse and present to the justice select committee in a number of "parliamentary petitions" later this year.

"What is clear is that almost all of the superinjunctions and hyperinjunctions have no public judgment," Hemming said. "That means that they are not compliant with the rules for a fair trial. There is also the question as to whether there should be an automatic time limit on an interim order. Many cases have an interim order and no final hearing. This is clearly wrong.

"We also need to know what the costs are both for the applicant and for the media in defending these orders. It is wrong to have a system whereby people can buy the sort of justice they want. That is a contravention of clause 29 of Magna Carta 1297, which is still in force."

Hemming is asking anyone who is subject to a gagging injunction that they would like to be included in the review to forward the information to him at the House of Commons.