A group of 48 US states have launched an antitrust probe against Alphabet-owned Google over its outsize dominance of online advertising with only the states of California and Alabama breaking the show of unity.

The investigation is being led by Texas attorney general Ken Paxton who has stated his desire to get to the root of Google’s ‘overarching control of online advertising markets and search traffic that may have led to anti-competitive behaviour that harms consumers.’

The move to invoke the courts highlights the growing scrutiny of government on the activities of technology giants amid fears that free search functionality has come at the cost of being able to locate the best products and companies.

In response legislators are seeking to ‘level the playing field’ and help reintroduce competition to a sector in which Google currently enjoys a near-monopoly, fueling accusations that it is drawing consumers to its products ahead of rivals.

To commence proceedings Google has been asked to hand over documents pertaining to its ad business with the expectation that the scope of the investigation will swiftly escalate to encompass other issues such as data privacy.

Google’s legal difficulties dovetail with a similar investigation into Facebook which has not been short of its problems to seek in the realm of data privacy.

Alphabet has said it is cooperating with the probe and had no further comment.

The US move follows a warning from Australia that Google and Facebook can expect stricter regulation and a €2.4bn antitrust fine from Europe.